From a fellow over-enthusiastic DIYer, I can't praise this video series enough. Impressed by the amount of research you have done and the knowledge you've gained. Love the level of detail, the explanations, the commentary, how informative they are - love it all....except for the music of course! 🤣
Mate, this is the most comprehensive ‘how to’ I’ve seen on TH-cam. Love that you cover the ‘why’ of the decisions you’ve made along with the other options available. Thank you
Hi Ali, You are amongst a few amateur DIY builders who explain everything in its most practicable form. I've watched from part 1 to part 6, and i feel confident that with your advise and instructions i can follow what you have made. Thanks for making it easy for us all. Keep up the good work.
Thanks Tony, they were a bit sketchy editing wise at the beginning but glad the info has come through clear. This is a very doable project with a bit of thought and planning :)
This video is (the whole garden room/workshop videos) about 3 years old but still the most comprehensive video on TH-cam. Going to start my project soon and i am a novice at this but your videos have truly inspired me to do it myself rather than getting someone in to coming in a doing it. My project will be smaller as i am looking at 4m x 3m but some great ideas between you and 'rag n bone brown'. thanks
What a fantastic tutorial, these videos have given me the confidence to have a go at a much smaller but similar project. Thanks for taking the time to make these videos to such a high standard.
This was just what I've been looking for. I'm about to pull up my floorboards, level everything, and then install the insulation and plywood as you did here, before replacing the hardwood on top. It seems that every video I've watched up until this point left out something! Thank you very much!
I've been a carpenter/joiner/cabinet maker for over twenty years and I have to say for a lay man you have good skills. I build a 500 sq ft workshop in much the same style as this.
Amazing helpful job. Thanks for all the details mentionned. I'm going to do approximatly the same for a 4 by 4 meter tiny house. I think I'll use a 45 x 120 mm that should be enough.
Been looking through TH-cam for some real guidance on building my cabin. Was looking for how to create the timber frame. Your videos and in depth explanations are excellent. Thanks.
Your videos are fantastic. I've been watching videos on garden room building for a long time now as I want to build one also. Your videos are by far the best I have seen. My main concern was how to approach the foundations and floor structure. Your videos have helped allot with that. So Thankyou and please keep them coming. Looking forward to the next one!
(In case it's of use to others who go down the rockwool insulation under the floor. I found a tarp worked well. You have to drape it over the joists though and support it underneath. If I made my shed again I would use celotex type insulation but its was not so easily available 20 years ago. I would like to say thanks to Ali, so informative. I'm going to build an extension soon. The way its been built so well on a very tight budget is just the impetus I need.
Great set of videos, just embarking on a garden office build in light of the current Pandemic, not in the building trade myself, but these videos make it understandable - about to complete the floor and move on to Part 7 - Many, many thanks...
That's great to hear Ian! Defo watch all the way through the series before starting as everything in the build is interconnected and there are lessons later on which apply here.
@@AliDymock yeah have watched right through a number of times and make a work breakdown and checklist as I go through so as hopefully not to miss anything. BTW: Did you make a video that covered cladding the building. Thanks again...
Absolute legend the girlfriend and I wanted a extension on the house but found it will be cheaper to jst build a summer house down the bottom of the garden and your videos are exactly what I have been looking for can't wait to see it done. Keep up the good work buddy cheers.
We were planning a garden office / shed area in a L-shaped formation and although we are complete novices we (well the other half) is very hands on when it comes to DIY. We watched 00s of online videos but nothing comes close to the comprehensiveness of these videos! So informative, well thought out, easy to follow and tbh, it has inspired me to get my hands dirty (will have to do the nails later!). Ali, thank you, subscribed and really looking forward to watching all the videos. Thank you again!!
That's fantastic Tahera. It's great fun, especially if you do it with your other half, and will save you a ton by doing it yourselves. Thanks for the comments too!
Definitely protect the exposed cut edges of the flooring, on all edges! Especially as the external walls are going to sit on the flooring?? Also, no need to leave gaps on the flooring sheets. Plywood is STABLE and does not expand and contract - due to 90° thin layers and glue. Brilliant series. Just come across your series, and loving it. Going to binge the lot!😂😂 Selling my house to buy something run down to do up, and set up my own garage workshop like this. Great series! Would it be worth revisiting with new cost options? One thing i didn't understand from early permitted developments - how can you have a 3m roof mono pitch, with a max 2.1 ceiling joist? 3m back wall to a 2.1m front wall, with sloping roof?? Also, from memory where is datum taken from to measure heights?? My back garden slopes up from the house!🙄
This is so informative and very clearly explained. I also appreciate all the maths and wise words of precautions on various points. Looking forward to seeing more as this is pretty much the kind of thing I want to build too, although it will be on a slight slope.
Hi Ali Paul again very impressive workmanship and attention to detail again in this video plywood was for sure your best option for this as a finished floor as osb doesn't have as nice of a flat nice surface and plywood is a better overall finish i also like the way you done your jig for fitting your insulation also i would like to note you done a good job using the expanding foam a lot of tradesmen would not have went to the effort of doing that so well done there really enjoying your progress and attention to detail brilliant.
I've just started looking at building something similar and have to say thus is the most comprehensive guide I've seen to date! You've already answered most of the questions I've had, thank you very much.Well done!
Watched all your vids, very informative and by far the best vids of this type I've seen so far and I've watched many to get an idea how to build my shed... Keep it up mate. Look forward to the next one....
great series, I wish I had seen this a few years ago, I have a steel shed I need to insulate and thinking about the options on the concrete floor and whether I need the walls and roof to be cold , or fully insulated, and the moisture requirements .
Great video series Ali. Just one thing for people to be aware of and that is that you don't get the insulation benefit from the aluminium foil covering of Celotex unless you have an air gap between that reflective cover and the next material. So where you lay the plywood directly on top of the Celotex you aren't getting that benefit from the product but you are still achieving the "U" values you were after. The reflective benefit can come in cavity walls where there is still an air gap between the Celotex and the brickwork.
Thanks Neil. The main reason for taping the floor was a vapour barrier but had hoped it would reflect infrared radiant heat back towards the building too. Do you know why it need the air gap around it exactly?
Ali Dymock yes it is back to your GCSE Physics lessons on heat transfer. Essentially three types Conduction, convection and radiation. Conduction is the most efficient so when things are touching then this will be the primary form of heat transfer. With your celotex it is touching the reflective surface which is touching the ply which is touching the flooring so the heat will move backwards and forwards through the materials via conduction. For the reflective/radiant barrier to be efficient at all and not dominated by the convection then you need to break the conductive link. You do this with an air gap minimum an inch. This allows the reflective material to reflect the radiant heat back. You can test this with a frying pan on the stove. Obviously if you put your hand on it it will burn if you put your hand six inches away you will feel a strong heat but if you put a bit of tin foil in between you won’t feel the heat. Put the tin foil directly in the pan and it conducts the heat like the rest of the pan and your hand will feel hot again! The celotex and tape does a good job as a vapour barrier though and the celotex as a pure non-conductive material does a good job too.
@@neiljpearce This is interesting and too late for my build as my floor has been constructed using Ali's videos as an instructional guide. Neil Pearce - if I apply your method to my walls, won't I need some form of ability for air to actually get INTO the walls to circulate in the first place? I've not even bought any PIR for my walls yet as I'm waiting until I've routed my cabling for electrics, but I too have used 4x2 stud walling. The 4x2 actually measures a depth of around 95mm so was intending buying 90mm PIR, however, based on your info I would need to go a lot thinner than that to gain a sufficient 'gap' for air, and then I would need to look at how I get air into the walls to circulate like the roof. I'm using your 'air gap' method for my 'cold roof' system (unlike Ali, I don't have the ability to build up to use a 'warm roof' option due to Permitted Developments), and will have vents at the front and back between my roof joists and the gap over my PIR for air to circulate.
Great videos, I've nearly finished my (tiny) garden room but i WISH I'd seen these earlier....builders assume you just know all this stuff! very informative, thanks
I’m hooked watching these. Feeling very inspired to also build one of these perhaps on a slightly smaller scale. Thank you very much for all your clear and insightful videos. Much appreciated.
I can see from the last pic of the vid, the build is wet from rain by the looks of it. Are the materials used in the vid generally OK to be outdoors and exposed to the elements for a short time? I'm considering my own build and curious about how long I have to put into it before erecting a roof to help keep the bulk of rain away
Hi Ali, Enjoying the videos. I am just going to construct a garden room. I am going to construct a floor like yours but concerned about rodents getting into the PIR from underneath.
Just for future reference, OSB 3 is more weather resistant than ply, and if taped also acts as an air barrier. Although unless treated with an anti slip coating, it is lethal for flooring in wood workshops when sawdust is on it. :o
Is there any realistic concern of elements or animals messing up foam board insulation? It crossed my mind to put some treated 1/2in ply underneath the insulation, but I'm not sure if that's overkill. I want to get the floor right, because I'll have no crawl space to make changes once I build on it.
Hi, I’m converting half my single brick garage into a games room (approx 4x4 metres), do you think it’s necessary to insulate all walls, floor and ceiling? Would too much heat be lost if I just insulted the floor and ceiling?
Hi Ali - love your work here....we've just started our log cabin in the forest....quick question, floor insulation going in this week.... You mentioned that foil-backed PIR needs 'several centimetres space above it' to properly reflect the heat back up. I've battened out my joists to make the insulation flush...worth re-doing this? It'll make sealing each joist bay more difficult.. Thanks!
I’m currently replacing a rotten floor on an insulated out building in manitoba where winters can be as cold as minus 40! Planning to replace insulation with styrofoam. Is an inside vapour barrier necessary?
Great video series. I am using your videos and principles used to build a glamping pod. Can I ask why you say 'don't use chipboard' for the floor? Thanks in advance.
Hi Ali, I love this series of videos, you've inspired me to build a Log cabin at the end of the garden and I'll be using the same "Block and wooden frame base construction as you. In this video you mention about not using Chipboard Flooring but, don't give a specific reason why? I was thinking of using Egger Protect Coated weather Resistant Chipboard flooring.
Yes I was thinking the same. I will be using a DPM over the top to keep it dry until I have my roof on. Egger protect is no longer available that’s y I’m using a different brand but keeping the DPM on it
Hello Ali, I’ve watched your vid numerous times and yep you’ve convinced me to give it a go myself.I’m going to be making the same size 30m2 so would you please be able to tell me what quantities of materials I need. Thanks
Thank you Ali for these wonderful detailed videos of your garden room. Just about to start a very similar build and the information you have shown helps and supports my thinking brilliantly. Looking forward to the remaining videos. Regards
Hi Ali, I am doing a proect and was wondering, if there will be a vermin issue if the insulation (celotex) is open to elements when sitting inside the timber frame.
Hi. Thanks for these videos. Great source of information. I have a couple of questions if I may. On the video of the span stats, you said about when choosing the depth of your timber, this would effect the thickness of your flooring on top. I don't think you mentioned it again. ? I was hoping to go with the first one on the chart for the floor. 38mm by 97mm at 600mm centres which means I have to set my blocks at no more than 1.3m apart. I'm fine with that as blocks are virtually free lol. Will I be OK with 18mm thick osb or ply on top? I was thinking of rubber strips on the joists to help sound proof and also get to the magic 100mm for my PIR insulation. Also, can the walls be erected straight onto the frame and not the osb ? If why not. Many thanks and thanks for your time...
Some one said to me burr ooo no insects love PIR board and the bottom of the base should be sealed. I haven’t done this, I’ve done the same as you. Have you heard this re insects and if so did you take it into consideration?
Agree with all the comments here, really informative vids so thank you! - considering there are so many people doing something similar it’s surprising how little decent info there is out there. A lot of it seems to contradict each other, especially regarding breathable membranes for walls, so looking forward to seeing how you went about that?
It's a popular trend right now for sure! There is some wrong info out there but a lot of it is subjective and there's no right way, so it's best not to get hung up on it. Other than the foundations I'm building mine properly, like they build a house in the US, with few shortcuts or cost savings but everyone has a different need so there's little wrong with doing things differently. No doubt as more people find this video there'll be people disagreeing with this or that. As for the breathable membrane-see sneak peak in Part 3-you can see the Tyvek housewrap - proper stuff!
Hi Ali, Just a quickie..... Do you have any "bounce" in your floor? I'm thinking of building a snooker room 8m x 5m. A 12' x 6' snooker table can weigh anything from 1200kgs to 1800kgs spread over 8 legs and I'm wondering if the pier foundations would be OK? Great series by the way really informative.
Hi, excellent video series, I was curious that the underside of your floor insulation was exposed are you not concerned about moisture or rodents getting into the PIR? Thanks
Cheers Richard. Moisture: - nope, the space below allows air flow to remove moisture, just like in a house Rodents: - again no, they don't really get into PIR and would struggle to climb up there. It's honestly no different to how a house's floor is made (just better insulated!)
Hi Ali, one question. How do you protect underneath the floor section? I.e. If I was to look up from underneath, would I see bear joists and PIR or did you protect it?
Great series of videos thanks! I am in the planning stages of a similar but smaller project. I need planning due to being in a national park, so hopefully no 2.5m height limit. What do you think of using a floating floor with the PIR on top of the subframe rather than between the joists to save the trouble of cutting it?
Just found this series, really helpful as it's almost exactly the same as what I'm currently building. One thing that's bothering me though is whether or not a ply floor will stand up to the rain while I'm building it? I think my ply is the same as yours, but I've already noticed a bit that seems to be de-laminating on the edge and it's been under a tarp since I got it a few weeks ago! I'm also concerned about standing the walls on the ply floor as that would make it impossible to replace in future. Any thoughts? Is it worth bringing it inside the walls perhaps (that would involve fitting a load of noggins for it to rest on)?
Hi Ali, we are building ours and have sized it to be 3 full board sheets - would you still stagger the boards or just lay them fully down. Seems odd to cut one just to offlay? cheers
You mean the long side of the ply? Generally this doesn't need support, adding in noggins in a straight line exactly where the side of the ply is can be done but that's a lot of noggins. 18mm ply spanning 400mm/16" joists will feel pretty firm. It's the same in your house, floorboards aren't supported at the sides, even before tongue and groove came along.
I wonder if you're THE Martin Freeman and are planning to build yourself a hobbit hole... I've put the time of year in the videos so you can see how quickly I got things done but as you say, it will vary from person to person and different projects and building methods. As for costs, I'll do a budget video at the end and then update the descriptions in each to say how much it cost to get to each stage :)
Really informative Ali, and thanks for including the costing diagrams, there are so many different options here in the UK and trying to weigh up cost against suitability is sometimes tricky. I am in the process of buying a new home, specifically chosen, as it excitingly, comes with a big double garage. Whoop! I really am excited as my current workshop is comparatively small. My plan is to build within a freestanding workshop and I have been researching the most cost effective insulation types, so a big thanks again, your experience here is a great help. I continue to be impressed by your workmanship, especially that snug fit cut, nice. How’s the new job going? Be sure to let me know if it falls through, I am known to make a cracking cup of builder’s tea! Btw, I do hope to see more from you here after the build is complete, your videos are interesting, fun and I am learning a lot. 👍🏼
Looking at my channel statistics, I think you're one of only a few women who have watched my videos! 😂 That sounds very feasible-by attaching timbers to the walls of the garage and then insulating in-between you'll be able to work in there all year round. Regarding workmanship- even if you pay an expensive builder firm, they won't take the care getting things like insulation nice and snug, so even though it was my first time doing it I know I get a better finish doing it myself. Job is going very well-sorry! Though if you lived nearby, happy to trade ideas for tea!
Ideally, I wonder if you were building the floor again would you put on battens of some sort for the PIR to sit down on a bit beyond the small battens put in place? Maybe they will do the job, but I'd like I think if i was doing it to see them sit down flush and tape from the underneath as well purely for the sake of overkill. But absolutely well done on ply over OSB. The fact that builders use OSB in areas of potential damp ingress boggles the mind.
Having watched the series about 10 times through now 😅 is this the part where you wouldn’t bother with the aluminium foil but use the polythene vapor barrier and wrap it under the plywood?
This is excellent. Could I ask how you knew the ground under the blocks wouldn't sink under the weight? (what constitutes good ground for laying down the hardcore). We have quite clay like soil. Thanks for the tutorial, really clear
Blind hope mostly 😉 I just got down to ground that felt undisturbed and really firm. Clay has it's issues but it's not going to collapse under your blocks. Go deeper, pour concrete first if you are worried though
Great video. Just wondered why you dropped the insulation 2mm lower than the joists? This would surely cause a shallow swimming pool to heat up in winter? I was thinking of placing my insulation 1mm above the joists, then when I screw the ply down on the joist, it would make sure the underside PLY touches the PIR and just slightly compress/bruises the PIR at the support battens when it compresses down 1mm. It would be great to know if you think this idea is an improvement or you had good reason to create the 2mm gap that will suffer 'wind wash' heat loss?
I wouldn't worry about the 'swimming pool' for heat. You;re right that that small space would heat up as well as it's above the insulation but it's not going to make a difference to the warmth of the building. I did mine like this so that the ply would rest on the joists not the insulation so where it's supported where it's screwed down. Going higher with the insulation may create a bounce if the PIR doesn't compress. Personally I wouldn't do this as the insulation isn't designed to support, especially in my case where it just floats and isn't supported below other than some battens. Hope that helps :)
@@AliDymock Many thanks in taking the time to reply. I've edited my previous comment for clarity. Having done this job myself for house underfloor insulation, I know for fact that when you screw the PLY down, the PIR simply gets squashed down 1mm by getting marked/bruised at the support batten. WRT you comment ref the PIR is not designed to support... they use PIR under concrete and on warm flat roof installations that you felt/rubber/fibre glass and walk over (where the PIR takes the load). With this installation, the joists take the load, which puts much less load on the PIR itself.
From a fellow over-enthusiastic DIYer, I can't praise this video series enough. Impressed by the amount of research you have done and the knowledge you've gained. Love the level of detail, the explanations, the commentary, how informative they are - love it all....except for the music of course! 🤣
Mate, this is the most comprehensive ‘how to’ I’ve seen on TH-cam. Love that you cover the ‘why’ of the decisions you’ve made along with the other options available. Thank you
Cheers Andy, thanks for the feedback, glad you’re finding it useful.
Hi Ali, You are amongst a few amateur DIY builders who explain everything in its most practicable form. I've watched from part 1 to part 6, and i feel confident that with your advise and instructions i can follow what you have made. Thanks for making it easy for us all. Keep up the good work.
Thanks Tony, they were a bit sketchy editing wise at the beginning but glad the info has come through clear. This is a very doable project with a bit of thought and planning :)
Best video hands down for this sort of work
This video is (the whole garden room/workshop videos) about 3 years old but still the most comprehensive video on TH-cam. Going to start my project soon and i am a novice at this but your videos have truly inspired me to do it myself rather than getting someone in to coming in a doing it. My project will be smaller as i am looking at 4m x 3m but some great ideas between you and 'rag n bone brown'. thanks
Great stuff! Well done for giving it a go
What a fantastic tutorial, these videos have given me the confidence to have a go at a much smaller but similar project. Thanks for taking the time to make these videos to such a high standard.
This was just what I've been looking for. I'm about to pull up my floorboards, level everything, and then install the insulation and plywood as you did here, before replacing the hardwood on top. It seems that every video I've watched up until this point left out something! Thank you very much!
I've been a carpenter/joiner/cabinet maker for over twenty years and I have to say for a lay man you have good skills. I build a 500 sq ft workshop in much the same style as this.
Amazing helpful job. Thanks for all the details mentionned. I'm going to do approximatly the same for a 4 by 4 meter tiny house. I think I'll use a 45 x 120 mm that should be enough.
Never have I come across a diy vid with such attention to detail...... you narration is impeccable. Perhaps you could get a job at the BBC?
Heheh thanks Adrian. You know, I did always want to be the next Attenborough...🤓
@@AliDymock Or Charlie Dimmock LOL
Excellent series of videos.
amazing and detailed explanations, so useful!
Been looking through TH-cam for some real guidance on building my cabin. Was looking for how to create the timber frame. Your videos and in depth explanations are excellent. Thanks.
Glad I could help!
Ive never come across such a good helpful DIY video on the whole of TH-cam. Thank you!
:)
Your videos are fantastic. I've been watching videos on garden room building for a long time now as I want to build one also. Your videos are by far the best I have seen. My main concern was how to approach the foundations and floor structure. Your videos have helped allot with that. So Thankyou and please keep them coming. Looking forward to the next one!
Thanks dude. You're not alone, the foundations were hardest for me too, took me ages to decide.
This is such a great video, thanks so much for sharing, this has helped me in doing a summer house for a friend
Fantastic design!!! I love this for every one
Wish I'd found these sooner! Currently renovating an outbuilding and this is really helpful 😁
Great videos. Just realised thats my local building merchants. They are good guys, love a shop where you can buy screws one at a time
Loving this series! Really appreciate the level of detail and editing behind every episode, thank you 👍
Glad you like them Fred!
Addictive...once you watch the first one you simply need to watch the rest...great upload.
(In case it's of use to others who go down the rockwool insulation under the floor. I found a tarp worked well. You have to drape it over the joists though and support it underneath.
If I made my shed again I would use celotex type insulation but its was not so easily available 20 years ago.
I would like to say thanks to Ali, so informative. I'm going to build an extension soon. The way its been built so well on a very tight budget is just the impetus I need.
The timing of finding this video is incredible for me. Thanks for creating this really useful video. Your build looks very similar to my plans.
Cool! Welcome to the channel Jamie!
Great set of videos, just embarking on a garden office build in light of the current Pandemic, not in the building trade myself, but these videos make it understandable - about to complete the floor and move on to Part 7 - Many, many thanks...
That's great to hear Ian! Defo watch all the way through the series before starting as everything in the build is interconnected and there are lessons later on which apply here.
@@AliDymock yeah have watched right through a number of times and make a work breakdown and checklist as I go through so as hopefully not to miss anything. BTW: Did you make a video that covered cladding the building. Thanks again...
Absolute legend the girlfriend and I wanted a extension on the house but found it will be cheaper to jst build a summer house down the bottom of the garden and your videos are exactly what I have been looking for can't wait to see it done. Keep up the good work buddy cheers.
We were planning a garden office / shed area in a L-shaped formation and although we are complete novices we (well the other half) is very hands on when it comes to DIY. We watched 00s of online videos but nothing comes close to the comprehensiveness of these videos! So informative, well thought out, easy to follow and tbh, it has inspired me to get my hands dirty (will have to do the nails later!). Ali, thank you, subscribed and really looking forward to watching all the videos. Thank you again!!
That's fantastic Tahera. It's great fun, especially if you do it with your other half, and will save you a ton by doing it yourselves. Thanks for the comments too!
Follwing keenly. Can't wait to see what you clad it with.
From start to finish I am glued to this channel. Brilliant again Ali, a big thumbs up from me. Regards Paul
Thanks Paul!
Super useful series. Thanks a lot!
Really like what you've [produced here with your step by step videos. Very professional and well researched. Thank You!
Thanks Jason!
Definitely protect the exposed cut edges of the flooring, on all edges! Especially as the external walls are going to sit on the flooring??
Also, no need to leave gaps on the flooring sheets. Plywood is STABLE and does not expand and contract - due to 90° thin layers and glue.
Brilliant series.
Just come across your series, and loving it. Going to binge the lot!😂😂
Selling my house to buy something run down to do up, and set up my own garage workshop like this.
Great series!
Would it be worth revisiting with new cost options?
One thing i didn't understand from early permitted developments - how can you have a 3m roof mono pitch, with a max 2.1 ceiling joist? 3m back wall to a 2.1m front wall, with sloping roof??
Also, from memory where is datum taken from to measure heights?? My back garden slopes up from the house!🙄
This is so informative and very clearly explained. I also appreciate all the maths and wise words of precautions on various points. Looking forward to seeing more as this is pretty much the kind of thing I want to build too, although it will be on a slight slope.
Glad you like it Tim. Yep mine was on a slope too. Have a look for my first 'Extra' video on that and related topics.
Ali Dymock Thanks, will do.
Really diligent. Everything done properly. Excellent series. Well done. Subscribed.
Hi Ali Paul again very impressive workmanship and attention to detail again in this video plywood was for sure your best option for this as a finished floor as osb doesn't have as nice of a flat nice surface and plywood is a better overall finish i also like the way you done your jig for fitting your insulation also i would like to note you done a good job using the expanding foam a lot of tradesmen would not have went to the effort of doing that so well done there
really enjoying your progress and attention to detail brilliant.
Thanks Paul, glad you like the series :)
I've just started looking at building something similar and have to say thus is the most comprehensive guide I've seen to date! You've already answered most of the questions I've had, thank you very much.Well done!
Great!
Watched all your vids, very informative and by far the best vids of this type I've seen so far and I've watched many to get an idea how to build my shed... Keep it up mate. Look forward to the next one....
Thanks for subscribing Tom, I'll do my best!
I'm sure you'll (:
Great video my friend
Another very insightful and clear video
great series, I wish I had seen this a few years ago, I have a steel shed I need to insulate and thinking about the options on the concrete floor and whether I need the walls and roof to be cold , or fully insulated, and the moisture requirements .
Great video series Ali. Just one thing for people to be aware of and that is that you don't get the insulation benefit from the aluminium foil covering of Celotex unless you have an air gap between that reflective cover and the next material. So where you lay the plywood directly on top of the Celotex you aren't getting that benefit from the product but you are still achieving the "U" values you were after. The reflective benefit can come in cavity walls where there is still an air gap between the Celotex and the brickwork.
Thanks Neil. The main reason for taping the floor was a vapour barrier but had hoped it would reflect infrared radiant heat back towards the building too. Do you know why it need the air gap around it exactly?
Ali Dymock yes it is back to your GCSE Physics lessons on heat transfer. Essentially three types Conduction, convection and radiation. Conduction is the most efficient so when things are touching then this will be the primary form of heat transfer. With your celotex it is touching the reflective surface which is touching the ply which is touching the flooring so the heat will move backwards and forwards through the materials via conduction. For the reflective/radiant barrier to be efficient at all and not dominated by the convection then you need to break the conductive link. You do this with an air gap minimum an inch. This allows the reflective material to reflect the radiant heat back. You can test this with a frying pan on the stove. Obviously if you put your hand on it it will burn if you put your hand six inches away you will feel a strong heat but if you put a bit of tin foil in between you won’t feel the heat. Put the tin foil directly in the pan and it conducts the heat like the rest of the pan and your hand will feel hot again!
The celotex and tape does a good job as a vapour barrier though and the celotex as a pure non-conductive material does a good job too.
Brilliant. I love an analogy. Might have to use that one in the video after next. Thanks for taking the time
@@neiljpearce This is interesting and too late for my build as my floor has been constructed using Ali's videos as an instructional guide.
Neil Pearce - if I apply your method to my walls, won't I need some form of ability for air to actually get INTO the walls to circulate in the first place? I've not even bought any PIR for my walls yet as I'm waiting until I've routed my cabling for electrics, but I too have used 4x2 stud walling. The 4x2 actually measures a depth of around 95mm so was intending buying 90mm PIR, however, based on your info I would need to go a lot thinner than that to gain a sufficient 'gap' for air, and then I would need to look at how I get air into the walls to circulate like the roof.
I'm using your 'air gap' method for my 'cold roof' system (unlike Ali, I don't have the ability to build up to use a 'warm roof' option due to Permitted Developments), and will have vents at the front and back between my roof joists and the gap over my PIR for air to circulate.
Great video and I'm enjoying the series.
This was so helpful. I'm going to be constructing a shed for tropical fish and I want to insulate it as best I can.
Great videos, I've nearly finished my (tiny) garden room but i WISH I'd seen these earlier....builders assume you just know all this stuff! very informative, thanks
Yeh they assume it's obvious stuff lol
Super video 👍
I’m hooked watching these. Feeling very inspired to also build one of these perhaps on a slightly smaller scale. Thank you very much for all your clear and insightful videos. Much appreciated.
:) it's definitely a doable project.
Love it, cant wait to start my garden room in the summer
I can see from the last pic of the vid, the build is wet from rain by the looks of it. Are the materials used in the vid generally OK to be outdoors and exposed to the elements for a short time? I'm considering my own build and curious about how long I have to put into it before erecting a roof to help keep the bulk of rain away
Great narrative.
Hi Ali,
Enjoying the videos. I am just going to construct a garden room. I am going to construct a floor like yours but concerned about rodents getting into the PIR from underneath.
Hi again Ali, another great vid. Love the channel and all the information within. Keep it up mate.
Thanks again Tom, will do!
Just for future reference, OSB 3 is more weather resistant than ply, and if taped also acts as an air barrier. Although unless treated with an anti slip coating, it is lethal for flooring in wood workshops when sawdust is on it. :o
Is there any realistic concern of elements or animals messing up foam board insulation? It crossed my mind to put some treated 1/2in ply underneath the insulation, but I'm not sure if that's overkill. I want to get the floor right, because I'll have no crawl space to make changes once I build on it.
Great videos and details. My own research has been cut in half. Thank you!
Nice work, bomb proof video!
Very helpful and appreciated. Thanks for video
Loving these videos - about to start my own project similar to this.
Hey man, does OSB needs room to expand too ? Or theses gaps are only for PLYwood method.
THANKS in advance
Hi, I’m converting half my single brick garage into a games room (approx 4x4 metres), do you think it’s necessary to insulate all walls, floor and ceiling? Would too much heat be lost if I just insulted the floor and ceiling?
Hi Ali - love your work here....we've just started our log cabin in the forest....quick question, floor insulation going in this week.... You mentioned that foil-backed PIR needs 'several centimetres space above it' to properly reflect the heat back up. I've battened out my joists to make the insulation flush...worth re-doing this? It'll make sealing each joist bay more difficult.. Thanks!
Cheers Ali, really helpful for my flat roof bathroom. Looking forward to the next chapter.
I’m currently replacing a rotten floor on an insulated out building in manitoba where winters can be as cold as minus 40! Planning to replace insulation with styrofoam. Is an inside vapour barrier necessary?
Great video series. I am using your videos and principles used to build a glamping pod. Can I ask why you say 'don't use chipboard' for the floor? Thanks in advance.
Hi Ali, I love this series of videos, you've inspired me to build a Log cabin at the end of the garden and I'll be using the same "Block and wooden frame base construction as you.
In this video you mention about not using Chipboard Flooring but, don't give a specific reason why? I was thinking of using Egger Protect Coated weather Resistant Chipboard flooring.
Yes I was thinking the same. I will be using a DPM over the top to keep it dry until I have my roof on. Egger protect is no longer available that’s y I’m using a different brand but keeping the DPM on it
Hello Ali, I’ve watched your vid numerous times and yep you’ve convinced me to give it a go myself.I’m going to be making the same size 30m2 so would you please be able to tell me what quantities of materials I need. Thanks
Thank you Ali for these wonderful detailed videos of your garden room. Just about to start a very similar build and the information you have shown helps and supports my thinking brilliantly. Looking forward to the remaining videos. Regards
What's your thoughts on mice etc trying to nest into the PIR boards?
thanks for this All..I was beginning to loose hope of comprehending what I need to start my building
You can do it!
@@AliDymock What sort of concrete blocks have you got
Hi Ali, I am doing a proect and was wondering, if there will be a vermin issue if the insulation (celotex) is open to elements when sitting inside the timber frame.
Hi. Thanks for these videos. Great source of information. I have a couple of questions if I may. On the video of the span stats, you said about when choosing the depth of your timber, this would effect the thickness of your flooring on top. I don't think you mentioned it again. ? I was hoping to go with the first one on the chart for the floor. 38mm by 97mm at 600mm centres which means I have to set my blocks at no more than 1.3m apart. I'm fine with that as blocks are virtually free lol. Will I be OK with 18mm thick osb or ply on top?
I was thinking of rubber strips on the joists to help sound proof and also get to the magic 100mm for my PIR insulation.
Also, can the walls be erected straight onto the frame and not the osb ? If why not.
Many thanks and thanks for your time...
really helpful
'Screws three times the width of the material'.. That made me laugh. Great vid thanks.
Some one said to me burr ooo no insects love PIR board and the bottom of the base should be sealed. I haven’t done this, I’ve done the same as you. Have you heard this re insects and if so did you take it into consideration?
Agree with all the comments here, really informative vids so thank you! - considering there are so many people doing something similar it’s surprising how little decent info there is out there. A lot of it seems to contradict each other, especially regarding breathable membranes for walls, so looking forward to seeing how you went about that?
It's a popular trend right now for sure! There is some wrong info out there but a lot of it is subjective and there's no right way, so it's best not to get hung up on it.
Other than the foundations I'm building mine properly, like they build a house in the US, with few shortcuts or cost savings but everyone has a different need so there's little wrong with doing things differently. No doubt as more people find this video there'll be people disagreeing with this or that.
As for the breathable membrane-see sneak peak in Part 3-you can see the Tyvek housewrap - proper stuff!
Hi Ali, Just a quickie.....
Do you have any "bounce" in your floor? I'm thinking of building a snooker room 8m x 5m. A 12' x 6' snooker table can weigh anything from 1200kgs to 1800kgs spread over 8 legs and I'm wondering if the pier foundations would be OK?
Great series by the way really informative.
Great video mate 👍
Very good again! When can we expect more ?
Thanks! I’m trying to keep to a bi-weekly schedule.
It’s the working out of how to present the information that takes the time...
That second hand PIR is very attractive. Shame they won't deliver to my address. 😕
Great thanks
Good work, glad I found this
Hi, excellent video series, I was curious that the underside of your floor insulation was exposed are you not concerned about moisture or rodents getting into the PIR? Thanks
Cheers Richard.
Moisture: - nope, the space below allows air flow to remove moisture, just like in a house
Rodents: - again no, they don't really get into PIR and would struggle to climb up there. It's honestly no different to how a house's floor is made (just better insulated!)
Thanks very much for the informative videos.
You have a new subcsriber!!
Hi Ali Top Videos which have helped me alot. Im currently at this stage at the moment.Celotex has just been delivered.Better crack on.Thanks again.
Enjoy! Don't forget the dust mark!
Hi Ali, one question. How do you protect underneath the floor section? I.e. If I was to look up from underneath, would I see bear joists and PIR or did you protect it?
Another great one. Keep it up!
Great series of videos thanks! I am in the planning stages of a similar but smaller project. I need planning due to being in a national park, so hopefully no 2.5m height limit. What do you think of using a floating floor with the PIR on top of the subframe rather than between the joists to save the trouble of cutting it?
Just found this series, really helpful as it's almost exactly the same as what I'm currently building. One thing that's bothering me though is whether or not a ply floor will stand up to the rain while I'm building it? I think my ply is the same as yours, but I've already noticed a bit that seems to be de-laminating on the edge and it's been under a tarp since I got it a few weeks ago! I'm also concerned about standing the walls on the ply floor as that would make it impossible to replace in future. Any thoughts? Is it worth bringing it inside the walls perhaps (that would involve fitting a load of noggins for it to rest on)?
Hi Ali, we are building ours and have sized it to be 3 full board sheets - would you still stagger the boards or just lay them fully down. Seems odd to cut one just to offlay? cheers
Why not use 'duvet' style insulation, multifoil layer stuff, I thought that outperformed PIR
Another question Ali please. At 9:05 i can see the plywood on the right side it didn’t fall on a joist, so what did you do in this situation?
You mean the long side of the ply? Generally this doesn't need support, adding in noggins in a straight line exactly where the side of the ply is can be done but that's a lot of noggins. 18mm ply spanning 400mm/16" joists will feel pretty firm. It's the same in your house, floorboards aren't supported at the sides, even before tongue and groove came along.
Very useful videos and explanations. Costs and timescales to do things would be helpful but understand that these are variables depending on project.
I wonder if you're THE Martin Freeman and are planning to build yourself a hobbit hole...
I've put the time of year in the videos so you can see how quickly I got things done but as you say, it will vary from person to person and different projects and building methods. As for costs, I'll do a budget video at the end and then update the descriptions in each to say how much it cost to get to each stage :)
+Ali Dymock unfortunately not the just one of many....but still considering a build.
He building will be excellent.
Really informative Ali, and thanks for including the costing diagrams, there are so many different options here in the UK and trying to weigh up cost against suitability is sometimes tricky.
I am in the process of buying a new home, specifically chosen, as it excitingly, comes with a big double garage. Whoop! I really am excited as my current workshop is comparatively small.
My plan is to build within a freestanding workshop and I have been researching the most cost effective insulation types, so a big thanks again, your experience here is a great help.
I continue to be impressed by your workmanship, especially that snug fit cut, nice.
How’s the new job going? Be sure to let me know if it falls through, I am known to make a cracking cup of builder’s tea!
Btw, I do hope to see more from you here after the build is complete, your videos are interesting, fun and I am learning a lot. 👍🏼
Looking at my channel statistics, I think you're one of only a few women who have watched my videos! 😂
That sounds very feasible-by attaching timbers to the walls of the garage and then insulating in-between you'll be able to work in there all year round. Regarding workmanship- even if you pay an expensive builder firm, they won't take the care getting things like insulation nice and snug, so even though it was my first time doing it I know I get a better finish doing it myself.
Job is going very well-sorry! Though if you lived nearby, happy to trade ideas for tea!
Would 25mm celetex do for a floor ? The floor will have a laminate with insulation underlay also
Ideally, I wonder if you were building the floor again would you put on battens of some sort for the PIR to sit down on a bit beyond the small battens put in place? Maybe they will do the job, but I'd like I think if i was doing it to see them sit down flush and tape from the underneath as well purely for the sake of overkill. But absolutely well done on ply over OSB. The fact that builders use OSB in areas of potential damp ingress boggles the mind.
What thickness Of Plywood Did You Use For The Floor?
The foil won't have the reflective effect unless there's an air gap in front of it. Thanks for these videos.
You're spot on. I didn't know that at the time. It seems like 5cm of air space is needed for that reflective radiation effect 👍
did you vent the void under the floor ??
Having watched the series about 10 times through now 😅 is this the part where you wouldn’t bother with the aluminium foil but use the polythene vapor barrier and wrap it under the plywood?
This is excellent. Could I ask how you knew the ground under the blocks wouldn't sink under the weight? (what constitutes good ground for laying down the hardcore). We have quite clay like soil. Thanks for the tutorial, really clear
Blind hope mostly 😉 I just got down to ground that felt undisturbed and really firm. Clay has it's issues but it's not going to collapse under your blocks. Go deeper, pour concrete first if you are worried though
Great video. Just wondered why you dropped the insulation 2mm lower than the joists? This would surely cause a shallow swimming pool to heat up in winter?
I was thinking of placing my insulation 1mm above the joists, then when I screw the ply down on the joist, it would make sure the underside PLY touches the PIR and just slightly compress/bruises the PIR at the support battens when it compresses down 1mm.
It would be great to know if you think this idea is an improvement or you had good reason to create the 2mm gap that will suffer 'wind wash' heat loss?
I wouldn't worry about the 'swimming pool' for heat. You;re right that that small space would heat up as well as it's above the insulation but it's not going to make a difference to the warmth of the building. I did mine like this so that the ply would rest on the joists not the insulation so where it's supported where it's screwed down. Going higher with the insulation may create a bounce if the PIR doesn't compress. Personally I wouldn't do this as the insulation isn't designed to support, especially in my case where it just floats and isn't supported below other than some battens. Hope that helps :)
@@AliDymock Many thanks in taking the time to reply. I've edited my previous comment for clarity. Having done this job myself for house underfloor insulation, I know for fact that when you screw the PLY down, the PIR simply gets squashed down 1mm by getting marked/bruised at the support batten.
WRT you comment ref the PIR is not designed to support... they use PIR under concrete and on warm flat roof installations that you felt/rubber/fibre glass and walk over (where the PIR takes the load). With this installation, the joists take the load, which puts much less load on the PIR itself.