This video is about our new flexible wood fibre insulation producty, SteicoFlex. Will Kirkman & Martin Twamley talk about Steicoflex, it's properties and how to use it.
Hi. The product contains Ammonium Sulphate which acts as a low-level fire retardant. The product will burn in a fire but it doesn't burn with a flame and generally smoulders so does not contribute to the fire. Ammonium Sulphate is largely inert an non-toxic and is used in food as an acidity regulator. Hope that helps.
Hi. Thanks for sharing this video, great info. Should a membrane be fitted between the flexible wood fibre insulation and plasterboard? If so, what sort of specification is suitable? Many Thanks
Hi Jack. Yes, usually a membrane should be fitted between the plasterboard and Flex to maintain airtightness and vapour regulation. We recommend the Ampatex Sinco from our range. Hope that helps.
Is this material suitable as a mineral wool replacement for DIY acoustic panels construction? I'm looking for a healthier alternative for mineral wool and this seems quite promising.
Hi. Yes, the Steicoflex is arguably better than most mineral wools as it is denser and wood fibres are slightly better at absorbing sound energy as well. This product is 60kg/m3 so you'd need a mineral wool of at least that density to improve on the Steicoflex. Hope that helps.
Hi, thank you for this. I’d have watched a number of van conversion videos and they use the Kingspan or Celotex on flooring between studs running on the van floor. Is it then covered with a 6mm or 9mm ply covering. Would this product work in the same way? I’m looking for a more natural product rather than the non natural alternatives
Hi Bruce. Yes, you can use this product instead of PIR boards for converting a van floor. We have it in 20, 40, 50, 60, 80, 100.... all the way up to 200mm thicknesses in stock. Hope that helps.
I've had an energy survey and advised to use wood fibre board for internal insulation in a 300 year old property with solid walls. Would the use of plasterboards counter the breathability of the Steico boards? Should i look for cork based plaster directly on to the boards instead?
Hi Lee. You certainly can use wood fibre boards for internal wall insulation in old houses but not this product. You'd need something like the Steico Internal boards or our UdiIN boards. You can plaster over the top of the boards with certain lime plasters or you can sometimes batten off and use a vapour control membrane and plasterboard. Plasterboard is perfectly breathable enough to be used with this construction but I would suggest you don't use vinyl paint over it once plastered. Please email us if you want to look at this more closely so that we can produce a specification for you. Hope that helps.
Hi Chris, we have bought a very old house 1909, the frame is like a log cabin. We need to insulate it from the inside. Shall we put the membrane on the wooden wall, then put SteicoFlex, and then the pasterboard? Thanks a lot. Or if there is any specifications how to install it somewhere, thanks for sharing the web.
Hi Zuzana. Thanks for your question. If you want to use the SteicoFlex you'd need to build a timber frame to install the material in to. Alternatively you can use the wood fibre boards which are rigid enough to either lime plaster directly on to or to fix a batten to and then mount plasterboard on to. Which option sounds best for you?
@@BacktoEarthLTD Thanks a lot. I think plasterboard is better as the room is going to be a bedroom and I would like a wallpaper :) I have been looking for a local seller around where we live. I found a company selling the product :) Thanks a lot for your reply
Hi @martbrandjes1213. I don't think this will be possible as the SteicoFlex is quite firm and would require a lot of pressure to do this. You could use 50 + 80mm and squash to 125mm though. Hope that helps.
Hi Chris - If this product was to be used to insulate a timber shed (walls and roof) is an airgap required behind the insulation. Current wall construction is timber cladding - batten/airgap - permeable moisture barrier - OSB3 - stud wall (exterior to interior) (and similar for the roof). Am i able to install the Steicoflex flush to the external OSB between rafters / wall studs then seal with a vapour control membrane & interior cladding or do i need another airgap? Thanks
Hi Jonny. If the OSB3 is on the outside of the studs and rafters then you don't need an air gap between the Steicoflex and OSB. You would need to install a vapour control layer (not vapour barrier) on the inner face of the studs before you apply whatever internal finish you decide to use but again, no air gaps required. However, if you plan to run wiring internally then this should not penetrate the VCL and so a cavity might be useful in front of the VCL, behind the internal finish. Hope that makes sense.
if i batten an external brick wall out that has no cavity. put this insulation in-between. and then plasterboard over. will it be ok or would condensation be a risk? i do not really want to lime plaster as its difficult. and from what I’ve heard these walls need to breath. would plasterboard be a no go?
Hi K. The SteicoFlex flexible wood fibre batts are not suitable for this application as they are not dense enough to manage the levels of moisture that you get in the wall. We do however have a plasterboard solution with a wood fire board that you can see here - www.backtoearth.co.uk/internal-wall-insulation-with-plasterboard-finish/ Hope that helps.
@@BacktoEarthLTD i seen on the website that plasterboard is actually breathable. most people say it isnt. but if water vapour can pass through it then surely it is?
@@user-cn1em2qx6f Absolutely. It is perfectly breathable, more so than most lime plasters actually. Just make sure you don't then apply vinyl paints as these are definitely not what I would class as breathable!
Hi Chris, I live in an old house with a basement, would this product be suitable for fitting between the floor joists? If so, what thickness would you recommend?
Hi Barra. You can use it in a suspended floor so long as you don't have bare earth underneath and there is adequate ventilation. We normally suggest using a breather membrane to go up and down between the joists and to support the insulation. Over the top you should use a vapour control membrane which can be taped to the walls around the perimeter to make the whole construction airtight. Hope that helps.
I have some spare Steicoflex from my soundproofing/insulation project. I don't want to throw away the spare, what else can I use it for in my flat? Any ideas?
Hi Maya. Thanks for coming back to me. If you can't put it in any stud walls or ceilings then....This is a bit of a long shot, but what about under the bath? Could help keep the water warm. Also, do you have a hot water tank that could do with extra insulation? Not my normal field of expertise so a bit limited on ideas. Hope that helps :-)
We have cavity brick walls with breeze blocks behind plasterboard. Can I put this product behind the plasterboard so it sits between the breeze block and plasterboard? Do I need to add anything extra?
Hi James. Are you saying that the plasterboard is on battens attached to the inner leaf of the cavity wall? You can fill this void if you do not have full fill cavity insulation but if your cavity is fully filled then you should not add any insulation. Hope that helps.
@@jamesthomas3772 Hi James. If the cavity is fully filled you cannot guarantee that moisture is not reaching the inner leaf of masonry from outside. If it is partially filled you can be much more confident that this is not the case. If you have moisture coming from the outside reaching the inner blockwork it may not be visible due to the heat from the interior of the building keeping it dry. Adding insulation would reduce this heat flow and prevent it from drying, eventually causing the insulation to slowly get wet and decay. Obviously I'm talking worst case scenarios here but I can't guarantee that you won't have any problems by using it in the way you wish to.
@@BacktoEarthLTD thanks for your response. Is sealed plasterboard not vapor barrier in itself that would prevent heat/air passing through to the inner leaf (breeze block) behind it? also would we not be able to tell if moisture was coming in from outside into the inner leaf (breezeblock) because there should be visible signs on the plasterboard attached to that inner leaf that's been there for years no? For reference there's been no heating on upstairs in the rooms for a year+ as the home has been empty and this is in Scotland
Hi. The SteicoFlex is either 385 or 575mm wide and 1220mm long. Please note the wall behind shows how the insulation fits into a timber frame, it isn't an example of how to insulate any particular kind of wall. If you'd like us to create a specification for you please let me know. Thanks. Chris.
But why would you pay for this when this product also needs a vapour barrier on the warm side? Unless you can guarantee that there will be no air gap between the external wall and insulation, i.e. by bonding the insulation to the external wall, then you can use mineral wool at 1/3 of the cost
Hi. Thanks for your comment and you're certainly not alone in not realising the benefits of using flexible wood fibre insulation over synthetic insulations like mineral or glass wool. If you're interested, please read our article on this topic - www.backtoearth.co.uk/news/wood-fibre-insulation-the-myths/ or we have lots of articles about the benefits of wood fibre insulation here - www.backtoearth.co.uk/news/. Hope that helps.
Hi. The product contains Ammonium Sulphate which acts as a low-level fire retardant. The product will burn in a fire but it doesn't burn with a flame and generally smoulders so does not contribute to the fire. Ammonium Sulphate is largely inert an non-toxic and is used in food as an acidity regulator. Hope that helps.
Hi. Thanks for sharing this video, great info. Should a membrane be fitted between the flexible wood fibre insulation and plasterboard? If so, what sort of specification is suitable? Many Thanks
Hi Jack. Yes, usually a membrane should be fitted between the plasterboard and Flex to maintain airtightness and vapour regulation. We recommend the Ampatex Sinco from our range. Hope that helps.
Who else is a grown-up watching videos on insulation? Alternatively growing up while watching videos on insulation.
Always useful to have an understanding of insulation!
Is this material suitable as a mineral wool replacement for DIY acoustic panels construction? I'm looking for a healthier alternative for mineral wool and this seems quite promising.
Hi. Yes, the Steicoflex is arguably better than most mineral wools as it is denser and wood fibres are slightly better at absorbing sound energy as well. This product is 60kg/m3 so you'd need a mineral wool of at least that density to improve on the Steicoflex. Hope that helps.
Hi, thank you for this. I’d have watched a number of van conversion videos and they use the Kingspan or Celotex on flooring between studs running on the van floor. Is it then covered with a 6mm or 9mm ply covering. Would this product work in the same way? I’m looking for a more natural product rather than the non natural alternatives
Hi Bruce. Yes, you can use this product instead of PIR boards for converting a van floor. We have it in 20, 40, 50, 60, 80, 100.... all the way up to 200mm thicknesses in stock. Hope that helps.
Does this need fixing against the wall? Or should I allow an airgap?
I've had an energy survey and advised to use wood fibre board for internal insulation in a 300 year old property with solid walls. Would the use of plasterboards counter the breathability of the Steico boards? Should i look for cork based plaster directly on to the boards instead?
Hi Lee. You certainly can use wood fibre boards for internal wall insulation in old houses but not this product. You'd need something like the Steico Internal boards or our UdiIN boards. You can plaster over the top of the boards with certain lime plasters or you can sometimes batten off and use a vapour control membrane and plasterboard. Plasterboard is perfectly breathable enough to be used with this construction but I would suggest you don't use vinyl paint over it once plastered. Please email us if you want to look at this more closely so that we can produce a specification for you. Hope that helps.
What chemicals are added to make it non-combustable?
Hi Chris, we have bought a very old house 1909, the frame is like a log cabin. We need to insulate it from the inside. Shall we put the membrane on the wooden wall, then put SteicoFlex, and then the pasterboard? Thanks a lot. Or if there is any specifications how to install it somewhere, thanks for sharing the web.
Hi Zuzana. Thanks for your question. If you want to use the SteicoFlex you'd need to build a timber frame to install the material in to. Alternatively you can use the wood fibre boards which are rigid enough to either lime plaster directly on to or to fix a batten to and then mount plasterboard on to. Which option sounds best for you?
@@BacktoEarthLTD Thanks a lot. I think plasterboard is better as the room is going to be a bedroom and I would like a wallpaper :) I have been looking for a local seller around where we live. I found a company selling the product :) Thanks a lot for your reply
OK, no problem. I'll let them take over. Good luck.
@@BacktoEarthLTD thanks a lot. im glad i have found the product as we live in sweden :)
Hi, my roof construction has 125mm depth. Could I compress the 140 mm to 125 mm thickness?
Hi @martbrandjes1213. I don't think this will be possible as the SteicoFlex is quite firm and would require a lot of pressure to do this. You could use 50 + 80mm and squash to 125mm though. Hope that helps.
Hi Chris - If this product was to be used to insulate a timber shed (walls and roof) is an airgap required behind the insulation. Current wall construction is timber cladding - batten/airgap - permeable moisture barrier - OSB3 - stud wall (exterior to interior) (and similar for the roof). Am i able to install the Steicoflex flush to the external OSB between rafters / wall studs then seal with a vapour control membrane & interior cladding or do i need another airgap? Thanks
Hi Jonny. If the OSB3 is on the outside of the studs and rafters then you don't need an air gap between the Steicoflex and OSB. You would need to install a vapour control layer (not vapour barrier) on the inner face of the studs before you apply whatever internal finish you decide to use but again, no air gaps required. However, if you plan to run wiring internally then this should not penetrate the VCL and so a cavity might be useful in front of the VCL, behind the internal finish. Hope that makes sense.
@@BacktoEarthLTD - That's great, thanks Chris!
if i batten an external brick wall out that has no cavity. put this insulation in-between. and then plasterboard over. will it be ok or would condensation be a risk? i do not really want to lime plaster as its difficult. and from what I’ve heard these walls need to breath. would plasterboard be a no go?
Hi K. The SteicoFlex flexible wood fibre batts are not suitable for this application as they are not dense enough to manage the levels of moisture that you get in the wall. We do however have a plasterboard solution with a wood fire board that you can see here - www.backtoearth.co.uk/internal-wall-insulation-with-plasterboard-finish/ Hope that helps.
@@BacktoEarthLTD i seen on the website that plasterboard is actually breathable. most people say it isnt. but if water vapour can pass through it then surely it is?
@@user-cn1em2qx6f Absolutely. It is perfectly breathable, more so than most lime plasters actually. Just make sure you don't then apply vinyl paints as these are definitely not what I would class as breathable!
@@BacktoEarthLTD thanks for ur help!
Hi Chris, I live in an old house with a basement, would this product be suitable for fitting between the floor joists? If so, what thickness would you recommend?
Hi Barra. You can use it in a suspended floor so long as you don't have bare earth underneath and there is adequate ventilation. We normally suggest using a breather membrane to go up and down between the joists and to support the insulation. Over the top you should use a vapour control membrane which can be taped to the walls around the perimeter to make the whole construction airtight. Hope that helps.
@@BacktoEarthLTD Hi Chris, thanks that is very helpful, any recommendations on thickness?
I have some spare Steicoflex from my soundproofing/insulation project. I don't want to throw away the spare, what else can I use it for in my flat? Any ideas?
Hi Maya. Thanks for coming back to me. If you can't put it in any stud walls or ceilings then....This is a bit of a long shot, but what about under the bath? Could help keep the water warm. Also, do you have a hot water tank that could do with extra insulation? Not my normal field of expertise so a bit limited on ideas. Hope that helps :-)
We have cavity brick walls with breeze blocks behind plasterboard.
Can I put this product behind the plasterboard so it sits between the breeze block and plasterboard?
Do I need to add anything extra?
Hi James. Are you saying that the plasterboard is on battens attached to the inner leaf of the cavity wall? You can fill this void if you do not have full fill cavity insulation but if your cavity is fully filled then you should not add any insulation. Hope that helps.
Hi Chris, it’s battens attached to breezeblock. Behind the breezeblock is a filled cavity, then brick. I want to insulate inside the battens
Why would you not insulate the battens behind the plasterboard if the cavity behind breeze block is insulated?
@@jamesthomas3772 Hi James. If the cavity is fully filled you cannot guarantee that moisture is not reaching the inner leaf of masonry from outside. If it is partially filled you can be much more confident that this is not the case. If you have moisture coming from the outside reaching the inner blockwork it may not be visible due to the heat from the interior of the building keeping it dry. Adding insulation would reduce this heat flow and prevent it from drying, eventually causing the insulation to slowly get wet and decay. Obviously I'm talking worst case scenarios here but I can't guarantee that you won't have any problems by using it in the way you wish to.
@@BacktoEarthLTD thanks for your response. Is sealed plasterboard not vapor barrier in itself that would prevent heat/air passing through to the inner leaf (breeze block) behind it? also would we not be able to tell if moisture was coming in from outside into the inner leaf (breezeblock) because there should be visible signs on the plasterboard attached to that inner leaf that's been there for years no? For reference there's been no heating on upstairs in the rooms for a year+ as the home has been empty and this is in Scotland
What size are the sheets and also what about behind the battons there needs to be a layer of insulation?
Hi. The SteicoFlex is either 385 or 575mm wide and 1220mm long. Please note the wall behind shows how the insulation fits into a timber frame, it isn't an example of how to insulate any particular kind of wall. If you'd like us to create a specification for you please let me know. Thanks. Chris.
@@BacktoEarthLTD so for a standard UK wall / loft with 400mm centres won't the 385 board be too narrow to friction fit?
R value?
Lambda is 0.036 W/mK. Divide the thickness (in metres) to get the R.
But why would you pay for this when this product also needs a vapour barrier on the warm side? Unless you can guarantee that there will be no air gap between the external wall and insulation, i.e. by bonding the insulation to the external wall, then you can use mineral wool at 1/3 of the cost
Hi. Thanks for your comment and you're certainly not alone in not realising the benefits of using flexible wood fibre insulation over synthetic insulations like mineral or glass wool. If you're interested, please read our article on this topic - www.backtoearth.co.uk/news/wood-fibre-insulation-the-myths/ or we have lots of articles about the benefits of wood fibre insulation here - www.backtoearth.co.uk/news/. Hope that helps.