Thermal bridge on ground floor under load bearing partition

[Canski]

  On 20/10/2022 at 09:05, Nickfromwales said:

Hope you're going with Beamshield / other for that B&B deck? Cold ventilated sub-floors are the last option if I specify a foundation system for a client!!

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Nope, I think I will be going with Litecast GT Same but different.

[Kelvin]

  On 20/10/2022 at 08:15, JohnMo said:

 

Not correct, from the marmox data sheet.

 

0.065m/0.078W/mK = 0.8mK/W convert to U value, 1/0.8=1.25

 

From the other datasheet

0.215/.15 W/mK = 1.43mK/W

convert to U value, 1/1.43=0.7

 

Thermolite is in fact nearly twice as good for reducing the heat loss, even with a worse conductivity.  Because they are 215mm high compared to 65mm. 

 

It's the size that matters!

 

 

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That's old data. The current thermal conductivity (according to the info I have) is 0.047W/mk which gives a U value of 0.72. In terms of the Thermolite block the compressive strength and dry density also matter. As far as I can see the Thermolite block with 0.15 W/m.K doesn't have either the compressive strength (3.6N/mm2) nor the density (600kg/m3) that's been specified for my build for example (7N/mm2 & 730kg/m3)

[Canski]

  On 20/10/2022 at 12:00, Kelvin said:

 

That's old data. The current thermal conductivity (according to the info I have) is 0.047W/mk which gives a U value of 0.72. In terms of the Thermolite block the compressive strength and dry density also matter. As far as I can see the Thermolite block with 0.15 W/m.K doesn't have either the compressive strength (3.6N/mm2) nor the density (600kg/m3) that's been specified for my build for example (7N/mm2 & 730kg/m3)

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They make 7N/mm2 thermalites  density of 730kg/m3 U value 0.18 W/m.K

[Kelvin]

  On 20/10/2022 at 12:08, Canski said:

They make 7N/mm2 thermalites  density of 730kg/m3 U value 0.18 W/m.K

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Yep got all the data on the various blocks. Just need to make a decision on what to do. 

[JohnMo]

  On 20/10/2022 at 12:00, Kelvin said:

That's old data. The current thermal conductivity (according to the info I have) is 0.047W/mk

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So they come with roughly the same u value, one is cheap, one isn't, your money your choice