Slab Insulation 'R' values for tonight.

LOL! I'd love to hear the answers you'd get if you went into a Wickes and asked that.

Most brands of insulation have similar R values for similar materials. I have figures for a few makes. Can you give any further details about it (i.e. polystyrene, polyisocyanate, mineral wool, whatever) as Wickes don't have any details on their pretty useless website.

Oh dear, thanks for replying, Peter, but I fell asleep. The items are in the catalogue and in the insulation pdf, but these two don't have the R value quoted. I would expect it to be on the outer shrink wrapping if you happened to have some. Ah well, another dawn, another day and off we go. Thank You Liz

In message , Liz writes

Ring Wickes?

Telephone: 0870 6089001

Do they quote a k value (thermal conductivity in W/mK)? If so then R is just the thickness (in metres) divided by k.

If we're talking about expanded polystyrene then k will be about 0.034 W/mK so, for the 50 mm material, R will be about 0.05/0.034 i.e. about

1.4 to 1.5 m^2K/W - and so on. The high density material will probably have a higher k value - 0.04 W/mK perhaps.

What! are you a secret salesman for the telephone company?

I've got half a pack of slabs of Wickes Flexi Insulation (Rockwool);

1125 x 600 x 50mm - is that the stuff?

R value is given as 1.30 m2K/W at 50mm

David

Liz the wickes insulation slabs are made to spec by knauf - the knauf absorption data is as below: Absorption co - efficients - S = Solid Backing - C = Cavity Rocksil Slabs Thickness RS33 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

40S 0.16 0.45 0.82 1.00 1.00 1.00 0.82 50S 0.10 0.60 0.90 1.00 1.00 1.00 0.88 60S 0.22 0.75 1.00 1.00 1.00 1.00 0.94 75S 0.24 0.53 0.89 0.94 0.96 0.98 0.83 100S 0.39 1.00 1.00 1.00 1.00 1.00 1.00

Thickness RS45 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

25S 0.05 0.25 0.55 0.75 0.9 1.00 0.61 40S 0.14 0.40 0.87 1.00 1.00 1.00 0.82 50S 0.25 0.65 1.05 1.10 1.05 0.95 0.96 75S 0.50 1.05 1.20 1.15 1.10 0.95 1.13 100S 0.80 1.15 1.20 1.15 1.15 1.00 1.16 50C 0.45 0.95 0.80 0.95 0.95 1.00 0.91

Thickness RS60

25S 0.10 0.20 0.65 0.85 1.00 0.90 0.68 40S 0.13 0.49 0.95 1.00 1.00 1.00 0.86 50S 0.25 0.65 1.05 1.10 1.10 0.95 0.98 75S 0.55 1.10 1.20 1.15 1.15 1.05 1.15 50C 0.45 0.90 0.80 0.90 0.95 0.95 0.89

Thickness RS80

25S 0.06 0.23 0.56 0.88 1.00 1.00 0.67 40S 0.14 0.61 1.00 1.00 1.00 1.00 0.90 50S 0.16 0.72 1.00 1.00 1.00 1.00 0.93 60S 0.25 0.90 1.00 1.00 1.00 1.00 0.98 75S 0.39 1.00 1.00 1.00 1.00 1.00 1.00 100S 0.59 1.00 1.00 1.00 1.00 1.00 1.00

Thickness RS100

25S 0.05 0.30 0.70 0.95 1.05 1.00 0.75 40S 0.12 0.44 0.88 1.00 1.00 1.00 0.83 50S 0.35 0.85 1.10 1.10 1.15 1.10 1.05 75S 0.44 1.00 1.00 1.00 1.00 1.00 1.00 50C 0.65 0.95 0.80 0.90 0.95 1.00 0.90

Thickness RS128 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

50S 0.40 0.90 1.00 1.00 1.00 0.95 0.98 50C 0.65 0.80 0.85 0.95 0.95 1.00 0.89

Thickness RS140 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

50S 0.40 0.90 1.15 1.05 1.10 0.95 1.05 50C 0.65 0.80 0.85 0.95 0.95 1.00 0.89

Thickness RS200 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

50S 0.40 0.50 0.70 0.70 0.70 0.70 0.65

Rocksil Insulation Mat Thickness 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

150 0.70 1.20 1.24 1.13 1.14 1.18 1.18 100 0.40 0.88 1.03 0.99 1.06 1.11 0.99 80 0.31 0.83 0.96 0.98 1.04 1.14 0.95 60 0.25 0.60 0.83 0.89 0.96 1.04 0.82

Rocksil Studio Mattress Thickness 125Hz 250Hz 500Hz 1000Hz 2000Hz 4000Hz NRC

50S 0.25 0.65 1.05 1.10 1.05 0.95 0.96 50C 0.45 0.95 0.80 0.95 0.95 1.00 0.91 S= Solid Backing - C = cavity the wickes general purpose slab will probably correlate to RS45 (45kg/m3) 50S (mm)and the heavy density slab to RS200 (yes 200kg/m3) but at 30mm as oppose to 50mm - i too was very interested to see this data - as far i can see it basically means the 50mm general purpose slab, much lower density will perform much better than the 30mm HD slab with the exception perhaps of the 125hz low frequency. The best of all for acoustic purpose would be the 85mm cavity wall slabs which at RS45 appear to be excellent performers, but surprisingly arent branded by wickes for the particular purposes of acoustic insulation - they seem to push the heavy density slabs when infact they arent the best performers, but are quite handy if your after saving an inch or two!! cheers ME Shaw

Liz wrote: