Identifying floor insulation

an_fathach · 26-01-2019 6:05pm #1

I have a new build, bought off the plans. According to the BER file it was built with 150mm Quinntherm in the floor, so the concrete floor is said to have a U value of about 0.13 W/m2K. The trouble is the concrete floor is pretty cold when exposed. We dont have underfloor heating. How can I go about finding out if there really is the Quintherm present?

Dakotabigone · 26-01-2019 6:06pm

Core a hole and take a sample.

an_fathach · 27-01-2019 1:25pm

Dakotabigone wrote: »

Core a hole and take a sample.

That sounds like a big job. What kind of trademans would do it and is it possible to DIY? Thanks a million!

notharrypotter · 27-01-2019 7:39pm

If you attempt it yourself as it is possible to damage the radon barrier or damp proof membrane if you are not careful.
While it may state product "a" on your blurb it would be acceptable if product "b" is used provided it provides an equivalent result.

This will then be a debate between your Engineer and the Builders Engineer.

an_fathach · 27-01-2019 9:47pm

notharrypotter wrote: »

If you attempt it yourself as it is possible to damage the radon barrier or damp proof membrane if you are not careful.
While it may state product "a" on your blurb it would be acceptable if product "b" is used provided it provides an equivalent result.

This will then be a debate between your Engineer and the Builders Engineer.

Interesting. Bearing in mind I know very little about this topic, I am not worried if a different product was used, I am just trying to assess if there is any floor insulation what so ever.

enricoh · 27-01-2019 9:53pm

Drill into it. Should be 100mm of concrete to drill through. Just use a 200mm bit.
I'd be very surprised if they didn't put in insulation.

an_fathach · 27-01-2019 10:09pm

enricoh wrote: »

Drill into it. Should be 100mm of concrete to drill through. Just use a 200mm bit.
I'd be very surprised if they didn't put in insulation.

I see. Thanks. I have an infrared thermoeter, could I roughtly estimate if it was present with it?

sydthebeat · 27-01-2019 11:44pm

an_fathach wrote: »

I see. Thanks. I have an infrared thermoeter, could I roughly estimate if it was present with it?

that wouldnt indicate any level of thickness of insulation..... it might just indicate performance.

Squall Leonhart · 27-01-2019 11:49pm

an_fathach wrote: »

I have a new build, bought off the plans. According to the BER file it was built with 150mm Quinntherm in the floor, so the concrete floor is said to have a U value of about 0.13 W/m2K. The trouble is the concrete floor is pretty cold when exposed. We dont have underfloor heating. How can I go about finding out if there really is the Quintherm present?

Having insulation below your slab isn't going to keep your concrete warm to the touch. When the house heats, the thermal mass of the concrete will absorb some of this heat, the insulation will prevent the heat escaping through the slab into the ground.

Without underfloor heating your concrete slab will not be warm, I think there's a slight misunderstanding on your part here.

As another poster stated. I'd be very very surprised, shocked really, if there was no insulation under your slab.

Lumen · 28-01-2019 6:21am

Why don't you test the u value directly?

Get a polystyrene box, bond it upside down to a thin plastic sheet, make a small hole and fill it with hot water, cork the hole, stick a thermometer through another part of the top, take timed measurements as the water cools, plot a graph, do maths.

edit: difficult to account for horizontal conduction, you'd need two different sized boxes to eliminate that variable

an_fathach · 29-01-2019 3:39pm

Squall Leonhart wrote: »

Having insulation below your slab isn't going to keep your concrete warm to the touch. When the house heats, the thermal mass of the concrete will absorb some of this heat, the insulation will prevent the heat escaping through the slab into the ground.

Without underfloor heating your concrete slab will not be warm, I think there's a slight misunderstanding on your part here.

As another poster stated. I'd be very very surprised, shocked really, if there was no insulation under your slab.

That is the advice I was looking for. Just for reference sake, in the what year did floor insulation become the norm?

Lumen wrote: »

Why don't you test the u value directly?
Get a polystyrene box, bond it upside down to a thin plastic sheet, make a small hole and fill it with hot water, cork the hole, stick a thermometer through another part of the top, take timed measurements as the water cools, plot a graph, do maths.

edit: difficult to account for horizontal conduction, you'd need two different sized boxes to eliminate that variable

That is a very creative approach. I would love to try this!

GreeBo · 29-01-2019 3:46pm

Squall Leonhart wrote: »

Having insulation below your slab isn't going to keep your concrete warm to the touch. When the house heats, the thermal mass of the concrete will absorb some of this heat, the insulation will prevent the heat escaping through the slab into the ground.

Without underfloor heating your concrete slab will not be warm, I think there's a slight misunderstanding on your part here.

As another poster stated. I'd be very very surprised, shocked really, if there was no insulation under your slab.

If its insulated then the floor should eventually get to ambient temperature, no?

Squall Leonhart · 29-01-2019 3:59pm

GreeBo wrote: »

If its insulated then the floor should eventually get to ambient temperature, no?

Technically, over time, yes.

I think it won't feel warm to touch though.. An example, tiles and carpet can be the same temperature, yet walking barefoot on tiles feels colder due to thermal conductivity of both materials. Carpet in this case being a poor conductor of heat, but good insulator and vice verse for the tile.

Calahonda52 · 29-01-2019 7:32pm

GreeBo wrote: »

If its insulated then the floor should eventually get to ambient temperature, no?

No

Insulation does not eliminate heat loss it only slows it down.

key factors in the rate of temp gain in the floor include:

the delta T at issue
the specific heat capacity and density of the heat transfer medium
the decrement delay characteristics of the insulation.

So if your heat transfer medium is air, at a ground temp of maybe 18 degrees or less, and a slab temp of 12 degrees and an "XPS/EPS" type of insulation under maybe a 100mm slab of concrete, it will never happen.

rayjdav · 29-01-2019 7:53pm

New build as of when??
There would be certificates from a professional involved that should state that the house was built in accordance with Building Regulations. This is a pretty basic regulation. Chase up the certificate, assuming that your solicitor has acquired same for the bank, which they insist on pre-draw-down of mortgage?
Core the floor at your own peril just to satisfy a curiosity....

an_fathach · 29-01-2019 8:53pm

rayjdav wrote: »

New build as of when??
There would be certificates from a professional involved that should state that the house was built in accordance with Building Regulations. This is a pretty basic regulation. Chase up the certificate, assuming that your solicitor has acquired same for the bank, which they insist on pre-draw-down of mortgage?
Core the floor at your own peril just to satisfy a curiosity....

Last two years.

There is depression patch under the sink where are of the floor is crumbled and I will see if I can dig that out without damaging the intact concrete.

Markcheese · 30-01-2019 2:26pm

an_fathach wrote: »

Last two years.

There is depression patch under the sink where are of the floor is crumbled and I will see if I can dig that out without damaging the intact concrete.

Eh, I think I'd be getting someone to look at that, before I messed with it,

an_fathach · 30-01-2019 6:36pm

Markcheese wrote: »

Eh, I think I'd be getting someone to look at that, before I messed with it,

It is loose rubble in the kitchen, around where the pipes in the kitchen drain. Is it not supposed to be be loose? No messing needed to look into it.

sydthebeat · 30-01-2019 8:21pm

No it's not supposed to be loose

antiskeptic · 01-02-2019 1:08pm

enricoh wrote: »

Drill into it. Should be 100mm of concrete to drill through. Just use a 200mm bit.

Ensuring the 200mm is length rather than diameter

It isn't that hard: you need to be pushing on the drill to get through the concrete but be ready to stop it dropping through the insulation (assuming present) once your through the slab. Otherwise you'll puncture the membrane below

After that, you can use a smaller diameter drill bit, twisted by hand to work your way through the insulation. The membrane is pretty robust so you've have to be hamfisted to puncture it

I'd be very surprised if they didn't put in insulation.

#metoo

antiskeptic · 01-02-2019 1:10pm

an_fathach wrote: »

I have a new build, bought off the plans. According to the BER file it was built with 150mm Quinntherm in the floor, so the concrete floor is said to have a U value of about 0.13 W/m2K. The trouble is the concrete floor is pretty cold when exposed. We dont have underfloor heating. How can I go about finding out if there really is the Quintherm present?

I know my current floor has 4" of insulation. The tiles feel cold. My last house had no insulation under the kitchen slab. The tiles felt like ice.

GreeBo · 01-02-2019 1:41pm

antiskeptic wrote: »

Ensuring the 200mm is length rather than diameter

It isn't that hard: you need to be pushing on the drill to get through the concrete but be ready to stop it dropping through the insulation (assuming present) once your through the slab. Otherwise you'll puncture the membrane below

After that, you can use a smaller diameter drill bit, twisted by hand to work your way through the insulation. The membrane is pretty robust so you've have to be hamfisted to puncture it

#metoo

Might be an idea to use a drill press if you have access to one, easier to control the depth and you could set some stops so you dont puncture the membrane

hesker · 01-02-2019 1:54pm

Identifying floor insulation

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