insulate existing concrete floor

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kobiak

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#272060 8-Jun-2020 10:08

Anyone have seen anything in NZ?

https://www.youtube.com/watch?v=7Leuu0OeoII

Something similar?

Currently: concrete + carpet underlay + carpet. Which does not help much to keep the ground level warm enough.

I want to insulate existing concrete floor on ground level. To be something like this:

- this bubble type insulation for concrete
- plywood
- underlay
- carpet/laminate

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#2500459 8-Jun-2020 11:29

There used to be wool based underlay product. I put it in my first house in Blenheim in carpeted areas (when re-carpeting) noticed a massive difference

Where I had tiles and lino, replaced with cork tiling with foam underlay, cork insulates very well and can be sealed with polyurethane. It dents under dining tables etc would be my only criticism

That was all over 10 years ago, property is a rental now and it's all still OK.

Mike

evilengineer

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#2500469 8-Jun-2020 11:45

The product is a vapour barrier, not insulation.

You might get a slight increase in R-value but it won't be much.

Only real way to get a decent bump would involve increasing the floor height by 50-60mm. (eg. battens/insulation or possibly dense polystyrene with a layer of ply on top).

Which then throws out all the door openings.

A thick underlay and carpet is probably as good as it's going to get, I reckon.

PS: Also worth noting that most heat loss happens around the perimeter where the slab edge meets the outside, not in the middle of the floor.

GeekRay

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#2500472 8-Jun-2020 11:49

evilengineer:

...

PS: Also worth noting that most heat loss happens around the perimeter where the slab edge meets the outside, not in the middle of the floor.

Are we able to insulate the perimeter in a retrofit manner? Thanks for your insights.

kobiak

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#2500487 8-Jun-2020 12:03

Thanks @MikeAqua, search for some cork underlay.

@evilengineer I've 25mm to work with before I need to change doors.

would some extra foam underlay 3mm + 5-8mm plywood change anything?

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kobiak

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#2500529 8-Jun-2020 12:42

Would something like this work?

https://www.bunnings.co.nz/expol-platinum-board-r0-47-2400x1200x15mm-insulation_p0281596 + laminate on top. I do I need plywood too?

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evilengineer

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#2500588 8-Jun-2020 13:16

GeekRay:

evilengineer:

...

PS: Also worth noting that most heat loss happens around the perimeter where the slab edge meets the outside, not in the middle of the floor.

Are we able to insulate the perimeter in a retrofit manner? Thanks for your insights.

Could be done. One option below:

https://www.insulfound.co.nz/

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Froglotion

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#2500732 8-Jun-2020 16:59

Is the carpet really cold or something?

kobiak

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#2500751 8-Jun-2020 17:57

Froglotion:
Is the carpet really cold or something?

Yes. It's not comfortable at all. It's not main living area, so 2 winters I did not even noticed. Now since working from home and my office on ground level - I can feel the cold :( temperature stays around 17-18 deg without heating when it's 8 deg or colder outside as of today's morning in West Auckland.

Heater heats the air and its get too hot to wait until floor is heated too :(

Current solution is shoes :) but meh I don't like it.

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Kickinbac

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#2501026 8-Jun-2020 22:23

Maybe reasearch using something like Marmox insulated board. This product design for under tiles but could be used. Check out the UK site as has more information on different uses. It’s basically XPS foam.
https://www.marmox.co.nz/product/multiboard/

andrewNZ

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#2501032 8-Jun-2020 23:18

May I recommend Glerups. Like better carpet you can take anywhere.

kobiak

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#2501159 9-Jun-2020 09:09

Kickinbac: Maybe reasearch using something like Marmox insulated board. This product design for under tiles but could be used. Check out the UK site as has more information on different uses. It’s basically XPS foam.
https://www.marmox.co.nz/product/multiboard/

That is exectly what I'm after. I tried mitre10/bunnings/placemakers in New Lynn, AKL yesterday to see and feel Expol H/X 10-15mm boards, but they told me these under special order and there's no way I could check these before purchasing.

Now I wonder if i order online/special order via shop. Will this be ok to install:
- concrete
- foam board 6-10mm
- laminate 8-12mm

Or do I need extra layer between foam board and laminate?

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Dulouz

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#2501161 9-Jun-2020 09:14

kobiak:
Yes. It's not comfortable at all. It's not main living area, so 2 winters I did not even noticed. Now since working from home and my office on ground level - I can feel the cold :( temperature stays around 17-18 deg without heating when it's 8 deg or colder outside as of today's morning in West Auckland.

Heater heats the air and its get too hot to wait until floor is heated too :(

Current solution is shoes :) but meh I don't like it.

Have you tried slippers?

Amanon

kobiak

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#2501206 9-Jun-2020 09:24

Dulouz:

Have you tried slippers?

Currently using one. I don't like slippers. I still hope, with extra insulation on the floor, it would be warmer overal. And floor in particular would feel warmer... Am I wrong? :(

THis morning outside 8.1 deg, ground level with no heating 16.6 deg (sensor is ankle high from the floor so it's around 1.5-2 deg warmer in the room).

Heating on, place around ~20 sqm gets warm, but floor is still cold :( and it's too hot to leave heater on :(

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timmmay

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#2501212 9-Jun-2020 09:29

kobiak:

Dulouz:

Have you tried slippers?

Currently using one.

Try wearing both, it'll help more!

timmmay

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#2501213 9-Jun-2020 09:29

kobiak:

I still hope, with extra insulation on the floor, it would be warmer overal. And floor in particular would feel warmer... Am I wrong? :(

THis morning outside 8.1 deg, ground level with no heating 16.6 deg (sensor is ankle high from the floor so it's around 1.5-2 deg warmer in the room).

Heating on, place around ~20 sqm gets warm, but floor is still cold :( and it's too hot to leave heater on :(

When I insulated under my wooden floor it made little difference to temperature or comfort, but that may be different for a concrete floor. Ceiling insulation made the biggest difference, wall insulation made a small difference, double glazing somewhere between the two. Removing downlights made a good difference.

The biggest thing we do is heat the house consistently in winter, so it warms through. Weekend and days we're home heating is on from 6am to 10pm, turned down a bit when we go out. Weekdays it's on 5am to 7am and then 3pm to 10pm, even though we're not home until 5pm. On super cold days we turn it down to 18 rather than off. Even though it's off a bit the house stays warmed through, so we're not heating it from really cold.

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