cold floor

The flooring guy came yesterday, broke a bit of the polystyrene off and confirmed it is Jablite (white balls compressed together by the looks of it). He suggested if concerned it may be worth just drilling a couple small holes in the chip board floor to see if runs through the property, the endoscope has not turned up yet.

I have purchased Quickstep Paso (click LVP from B&Q), The flooring guy suggested that for underlay we may be better off using the green wood fibre board as underlay and could help a little with cold coming through? I have just read on the fibreboard description though "Recommended to use in conjunction with vapour barrier polythene as a damp proof membrane. Not suitable for use with LVT (luxury vinyl tiles/flooring)" so guessing this not right for the job

I also previously emailed an insulation website for advice who have mentioned that this type of product may suit better?

https://www.insulationsuperstore.co...-acoustic-floor-underlay-12m-x-1m-x-10mm.html

I have had a look but dont think this would work ether as would be to spongey and would not support the joints of the clicks.

I think I will probably just end up going with Quickstep transit underlay.
 
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I have now taken up all the carpet and underlay, I can definitely feel a breeze coming from somewhere, I think it may the gap between the skirting and chipboard. Would it be best to silicone / caulk this first? I was then going to lay 6mm ply in living room/hall (to match what's down in the kitchen) then quickstep underlay / click LVT
 
Are you reluctant to pack mineral wool into the gap, especially round the edges of the room, to block the draught?
 
There’s not really anywhere to put the mineral wool.

I used an endoscope under the kitchen an looks like there is jablite (but no way of checking if they insulated all the way through without taking up all the chipboard

I’m not sure how I would go about taking up the chipboard as cannot see how they are fastened down (it looks like the chipboard was laid before the internal walls as goes under walls)

that’s why I was just wondering if sealing around the skirting and maybe between the chipboard joins would help
 

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if as I suspect, the "white polystyrene" is Jablite, then you should be aware that it has a higher R value than mineral wool (it is almost twice as effective as an insulator). It would be interesting to know whether or not you have any cold spots in the kitchen floor caused by gaps in insulation or missing insulation, but that would require an infra red (FLIR) camera or a phone attachment (unfortunately the cheapest clip on FLIR I've seen for Android phones is just under £200 - my Androifd phone endoscope in comparison was under £50). As far as insulating beneath the concrete. TBH, having thought about it, I'm unsure that you'd get a huge benefit from insulating the ceiling below the floor because you are insulating a concrete slab which should already be insulated above, so before going ahead with it I think I'd want to see what a thermal imager made of the floor. Incidentally, is the car parking below you enclovsed and if not is it very windy?

I have looked into an FLIR camera and have found I can rent an FLIR one pro for £30 a day locally, worth it?
 
Is it wo
I have looked into an FLIR camera and have found I can rent an FLIR one pro for £30 a day locally
is it worth the effort, put your face where you suspect gaps, you’ll soon know where the leaks are.

Fill with either. Rockwell rammed in or expanding foam.

You could fill the chipboard joints with sealant.
 
Is it wo

is it worth the effort, put your face where you suspect gaps, you’ll soon know where the leaks are.

Fill with either. Rockwell rammed in or expanding foam.

You could fill the chipboard joints with sealant.

that’s what I was wondering. Without taking the chipboard up there is not really anywhere to pack out with Rockwell/fibre

would there be much difference in using sealant/caulk/wood filler? Guess not
 
For cold no. For draughts yes.

Think JohnD was implying you could fill the skirting gaps if they are large, with rockwool, ram in with a scrapper for example.

As you have some insulation under the floor already, there is little point lifting the chipboard. You won't ever get a warm floor, unless you stick UFH in.
Try to get every gap filled where theres a draft, as it's the cheapest way forward.

The chipboard may not be fixed, might just be a floating floor, I'm guessing they are T&G boards?

If you could do something from your garage to stop the cold permeating this may help, but who knows.
 
I have looked into an FLIR camera and have found I can rent an FLIR one pro for £30 a day locally, worth it?
A FLIR camera will help you identify where the heat losses are. It can identify missing sections of Jablite (insulation) as well as poorly sealed joints. I think if it shows the whole floor to be relatively a lot colder than the rest of the room that you have an issue of the concrete slab becoming so cold (possibly due to conduction or convection) that it is drawing a lot of heat out of the structure. I did buy a cheap laser temperature sensor from LIDL to do something similar a few years ago - it was a lot more work than the FLIR camera, but it showed up where to insulate.

So yes, I think useful, however, you need to deal with draughts first (do you have any?). These can indicate poorly sealed joints, porous concrete, gaps between skirting and floor, gaps between skirting and wall, gaps around windows, etc. Didn't @JohnD make some suggestions about those? Go through the simpler to do stuff and employ the high tech only when you can no longer improve things, I'd say

Without taking the chipboard up there is not really anywhere to pack out with Rockwell/fibre
You already have Jablite in there which has higher performance than Rockwool/mineral wool so it won't achieve anything

would there be much difference in using sealant/caulk/wood filler? Guess not
Not wood filler (dries rigid) and ideally not caulk, silicone is better - even a 1mm gap can allow a draught. TMineral wool is better for big gaps as is low expansion foam. Time to get out the joss sticks (especially on a windy day) and find out where the draughts are, methinks (seriously!)
 
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this was what i had in mind. See pic.

my chipboard was ready for the skip anyway, as it had been walked on several times so was cracked.

The draught comes in round the edges of the room, so that's where you need to pack first and most thoroughly. mineral wool does not need to be cut to a precise fit, just stuff it in. Foam and slab will allow draughts if there are any gaps (there will be)

you can use the smoke from a joss stick to find draughts.

under a floor, if you have a gap, you can stuff mineral wool to fill it. It will prevent air movement as well as adding insulation, and will muffle noise a little. Unlike polystryrene or Celotex, it does not burn or give off poisonous gases in a fire.

It can be pressed to tightly fill irregular gaps, with no precision cutting needed.

Not much heat is lost through a floor, except for cold draughts. There is obviously no convection; little conduction if there is an air gap, next to no radiation.

Block any gaps you find, preferably with pink fire foam or mortar.

I also have a room over an unheated garage. Easy peasy.

View attachment 264224
 
For cold no. For draughts yes.

Think JohnD was implying you could fill the skirting gaps if they are large, with rockwool, ram in with a scrapper for example.

As you have some insulation under the floor already, there is little point lifting the chipboard. You won't ever get a warm floor, unless you stick UFH in.
Try to get every gap filled where theres a draft, as it's the cheapest way forward.

The chipboard may not be fixed, might just be a floating floor, I'm guessing they are T&G boards?

If you could do something from your garage to stop the cold permeating this may help, but who knows.

None of the skirting gaps are that large, maybe 1-2mm,

I tried lifting a board using a screw driver but I think they are T&G

I think once I have done as much as possible on the floor then the car port ceiling will be next job

A FLIR camera will help you identify where the heat losses are. It can identify missing sections of Jablite (insulation) as well as poorly sealed joints. I think if it shows the whole floor to be relatively a lot colder than the rest of the room that you have an issue of the concrete slab becoming so cold (possibly due to conduction or convection) that it is drawing a lot of heat out of the structure. I did buy a cheap laser temperature sensor from LIDL to do something similar a few years ago - it was a lot more work than the FLIR camera, but it showed up where to insulate.

So yes, I think useful, however, you need to deal with draughts first (do you have any?). These can indicate poorly sealed joints, porous concrete, gaps between skirting and floor, gaps between skirting and wall, gaps around windows, etc. Didn't @JohnD make some suggestions about those? Go through the simpler to do stuff and employ the high tech only when you can no longer improve things, I'd say


You already have Jablite in there which has higher performance than Rockwool/mineral wool so it won't achieve anything


Not wood filler (dries rigid) and ideally not caulk, silicone is better - even a 1mm gap can allow a draught. TMineral wool is better for big gaps as is low expansion foam. Time to get out the joss sticks (especially on a windy day) and find out where the draughts are, methinks (seriously!)

I think for £30 for the day its not bad just to get photos showing heat levels of the flooring and carport ceiling. I think once you have the photos you can look back over them on the phone software after returning the camera.

Just sitting in the living room with feet on the chipboard, the board itself is not feeling freezing at the time of writing but can feel air circulating so guessing its coming from the between the chipboard joints (think they are T&G so not sure how air tight that would be), or from the 1-2mm gap between the skirting and chipboard.

The reason I was thinking caulk may be the better option particularly for the chipboard joins is it can be sanded down so would still be flat in line with the chipboard, if using silicone it is more rubbery and difficult to smooth out. I am having 6mm ply applied over the chipboard so not sure if needed.

Maybe just silicone the 1-2mm gap between the skirting and chipboard first. See if still drafty then rent camera

would this be the best shout for both the chipboard joins and skirting ?

No Nonsense Wood Flooring Sealant Oak 310ml | Flooring Sealants | Screwfix.com


this was what i had in mind. See pic.

my chipboard was ready for the skip anyway, as it had been walked on several times so was cracked.

The draught comes in round the edges of the room, so that's where you need to pack first and most thoroughly. mineral wool does not need to be cut to a precise fit, just stuff it in. Foam and slab will allow draughts if there are any gaps (there will be)

you can use the smoke from a joss stick to find draughts.

the gaps are only ilke 1-2mm so not really space for mineral wall. I think sealant first around skirting then joss sticks, then camera
 
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I tried lifting a board using a screw driver but I think they are T&G

if you set a circular saw to 18mm cut, and draw a line a foot or two from the wall (or half-way over the joist, if parallel to the wall) you will find it surprisingly easy to cut out a strip that you can lift away, and screw back afterwards. you will need to add struts (noggins) to support any short edges

This is pretty sure to be the location of the draughts.

It's also a handy place to have access for pipes and cables.
 
Is 13 degrees in my flat at the mo, granted I have not turned the heating on :LOL:
 
if you set a circular saw to 18mm cut, and draw a line a foot or two from the wall (or half-way over the joist, if parallel to the wall) you will find it surprisingly easy to cut out a strip that you can lift away, and screw back afterwards. you will need to add struts (noggins) to support any short edges

This is pretty sure to be the location of the draughts.

It's also a handy place to have access for pipes and cables.

I would love to get the chipboard up to make sure its been insulated fully which I doubt but I think is a bit beyond my skillset (i dont have a circular saw)

I have used "wooden floor sealant" between to skirting and chipboard to see if helps with drafts.
 
so, it looks like i have drafts from all over the place
1. between skirting and chipboard - now sealed with wooden floor sealant
2. large gaps around pipework in cupboard for gas / water. - will get fibre insulation
3. behind radiators where the flexi hoses feed through the wall is just an open hole, no insulation - will get fibre insualtion
4. most of the chipboard is T&G but some of the boards flex in place so not T&G on one side so guessing the gap between the chipboard on the non T&G side is also drafty - might use wooden floor sealant, dont know if need to be fixed in place first as the movement may crack the sealant otherwise
6. under kitchen cabinets, blowing a gale
 
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