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Hi all,
To cut a long story short, I have a 17 year old extension that is much colder than the rest of the house. The floor in particular is really, really cold to walk on. I've taken a laminate board up, and underneath is some 4mm foam underlay straight onto concrete/screed. I have no idea if the builders that built the extension put any insulation under the screed/concrete, so I'm not exactly sure what could be causing the room to lose heat so quickly. Either way, it needs to be solved somehow!
I've done a lot of research into insulating the existing floor (removing and re-doing the concrete/screed would be too expensive), and am happy to put new skirting on at a greater height as well as trimming the doors, etc). Bearing in mind I only have about a 30mm increase in height before I'd have to muck about with the front door, I've come up with the following build-up:
-> Existing concrete/screed
-> Superfoil SFUF foil insulation (6mm)
-> Marmox Multiboard (20mm)
-> Timbermate XL underlay (3.6mm)
-> Existing laminate flooring
Total extra height = 26mm (the underlay is a similar height to the existing stuff).
The idea is that the foil insulation will be laid down on the floor first and go up the walls a little, behind the skirting boards in order to reduce any thermal bridging and also create a vapour barrier. The Marmox multiboards will provide the majority of the insulation, and due to the kPa of 400 and polymer cement layer, will provide enough of a solid surface for the underlay and laminate. My main concern is that the Superfoil insulation says it's effective without air gaps, but I've always read the opposite is true (of foil/foil insulation in general).
I would be very appreciative of any opinions you may have - I'm a DIY novice so I don't really have much of a clue about these things, but I do try my best to do jobs properly and thoroughly, so I've spent a lot of time looking into this. I understand that the idea is usually to heat the 'concrete slab' but this just isn't working because the room loses heat so quickly and the floor is ALWAYS cold. So this is my alternative solution without spending a fortune taking everything up.
Many thanks in advance.
To cut a long story short, I have a 17 year old extension that is much colder than the rest of the house. The floor in particular is really, really cold to walk on. I've taken a laminate board up, and underneath is some 4mm foam underlay straight onto concrete/screed. I have no idea if the builders that built the extension put any insulation under the screed/concrete, so I'm not exactly sure what could be causing the room to lose heat so quickly. Either way, it needs to be solved somehow!
I've done a lot of research into insulating the existing floor (removing and re-doing the concrete/screed would be too expensive), and am happy to put new skirting on at a greater height as well as trimming the doors, etc). Bearing in mind I only have about a 30mm increase in height before I'd have to muck about with the front door, I've come up with the following build-up:
-> Existing concrete/screed
-> Superfoil SFUF foil insulation (6mm)
-> Marmox Multiboard (20mm)
-> Timbermate XL underlay (3.6mm)
-> Existing laminate flooring
Total extra height = 26mm (the underlay is a similar height to the existing stuff).
The idea is that the foil insulation will be laid down on the floor first and go up the walls a little, behind the skirting boards in order to reduce any thermal bridging and also create a vapour barrier. The Marmox multiboards will provide the majority of the insulation, and due to the kPa of 400 and polymer cement layer, will provide enough of a solid surface for the underlay and laminate. My main concern is that the Superfoil insulation says it's effective without air gaps, but I've always read the opposite is true (of foil/foil insulation in general).
I would be very appreciative of any opinions you may have - I'm a DIY novice so I don't really have much of a clue about these things, but I do try my best to do jobs properly and thoroughly, so I've spent a lot of time looking into this. I understand that the idea is usually to heat the 'concrete slab' but this just isn't working because the room loses heat so quickly and the floor is ALWAYS cold. So this is my alternative solution without spending a fortune taking everything up.
Many thanks in advance.
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