June 2, 20215 yr Another of the multiple 'things I read and know but have now forgotten' ones here. Currently speccing insulation boards for contractor and can't quite remember why the more expensive Kingpsan Thermowall boards are better than the Celotex or Quinn equivalents when the given u-value for everything seems to be the same on all the data sheets. Any help appreciated!
June 2, 20215 yr If the stated insulation performance is similar, and the boards are available for sale and delivery , then price would seem to be the clincher. We had to have Kingspan (based in Leominster) for our shaped insulation (one of a few companies who provide shaped insulation), but for everything else, we used Ballytherm. Our BM gave us a reasonable discount. They thought that Kingspan was too expensive. All of it is similarly disgusting to cut and trim.
June 2, 20215 yr No difference. Now if you were comparing the Kingspan Kooltherm or other higher spec insulation there is a difference but not with the Kingspan thermowall. The biggest difference will be in the installation rather than insulation. A well installed insulation board with no gaps will perform much better than a poorly cut and fitted board.
June 2, 20215 yr 45 minutes ago, Dudda said: ... The biggest difference will be in the installation rather than insulation. A well installed insulation board with no gaps will perform much better than a poorly cut and fitted board. One of the steepest learning curves for me that was.... ? Am I glad I'll never ever have to do that at again. Ever.
June 2, 20215 yr Doing it at the moment - it's not fun! Bought an Bosch insulation saw blade for the jigsaw which produces no dust though.
June 2, 20215 yr 4 hours ago, Faz said: Bought an Bosch insulation saw blade for the jigsaw which produces no dust though. Don’t suppose you could link to those blades could you please? I’ll have a lot of PIR to cut in the next 3 months and reducing dust would be great!
June 4, 20215 yr This is what I bought mate - Bosch 2608635187 Soft Material Jigsaw Blade, 1 Lug, Black, Pack of 3: Amazon.co.uk: DIY & Tools Zero dust. They are 100mm blades but I am using them on 120mm PIR - just need to run the knife across the back of the board. I am making slow progress - keep getting called away or needing to jump in the forks to take a delivery etc. Not easy when you can't have a run at it.
June 5, 20215 yr 14 hours ago, Faz said: This is what I bought mate - Bosch 2608635187 Soft Material Jigsaw Blade, 1 Lug, Black, Pack of 3: Amazon.co.uk: DIY & Tools Zero dust. They are 100mm blades but I am using them on 120mm PIR - just need to run the knife across the back of the board. I am making slow progress - keep getting called away or needing to jump in the forks to take a delivery etc. Not easy when you can't have a run at it. Cheers. The reviews mention the blade is a bit thin and the bottom of the cut can be not square. Are you finding that?
June 5, 20215 yr On 02/06/2021 at 21:09, Big Jimbo said: That dust really gets stuck in the back of your throat. It’ll probably be the next asbestos- it’s horrific. Bit excessive but I have the festool PIR cutter that attaches to the extractor. Not cheap but worth it for a big job. I do lofts all the time but I’d still have one for a self build.
June 5, 20215 yr 1 minute ago, DragsterDriver said: It’ll probably be the next asbestos- it’s horrific. Bit excessive but I have the festool PIR cutter that attaches to the extractor. Not cheap but worth it for a big job. I do lofts all the time but I’d still have one for a self build. I have seen those. Very expensive, but they look the biz. Do they cut dust free when hooked up ?
June 5, 20215 yr 3 minutes ago, Big Jimbo said: I have seen those. Very expensive, but they look the biz. Do they cut dust free when hooked up ? not completely but I wouldn’t be without one, lifesaver especially on thick boards because it cuts so true. I think the worst dust is when you see people hammering on board between rafters when it’s clearly too tight ?
June 5, 20215 yr 11 minutes ago, DragsterDriver said: not completely but I wouldn’t be without one, lifesaver especially on thick boards because it cuts so true. I think the worst dust is when you see people hammering on board between rafters when it’s clearly too tight ? Yep, that's been me....Even with a mask on that stuff is a nightmare.
June 5, 20215 yr 33 minutes ago, Thorfun said: Cheers. The reviews mention the blade is a bit thin and the bottom of the cut can be not square. Are you finding that? Provided you press down on the jigsaw the cut is pretty straight. I don't get any dust at all. Small bit of stud and a lump hammer to smash the board in and job done - it is surprisingly time consuming though - the attic room I am doing is massive.
June 5, 20215 yr 51 minutes ago, DragsterDriver said: not completely but I wouldn’t be without one, lifesaver especially on thick boards because it cuts so true. I think the worst dust is when you see people hammering on board between rafters when it’s clearly too tight ? Sounds like me..... You can run a saw in between the truss and the board to ease it. Needs to be tight though otherwise it falls out. I run a length of tape after between the trusses and staple it to the timber to make sure it stays in place - easier now with the windows in so the wind won't rip through. All of the off cuts create the mess from hell though - keeping them for now as you sometimes needs small bits to fill awkward spaces.
June 18, 20215 yr I have a similar question in that I have ordered a large quantity of 150mm floor insulation from TP. They quoted me Reticel so I checked the p/a meets the u value I require which is 0.12 and it was fine. But on the invoice I see I have half 150mm Reticel and half Celotex coming. I can’t check if Celotex meets the u value because it gives an R value and I have no idea how to work that out. I’m sure it will be fine but would like to double check but don’t know how.
June 18, 20215 yr 34 minutes ago, John latimer said: it gives an R value and I have no idea how to work that out. https://www.ecowho.com/tools/r_value_to_u_value_calculator.php
June 21, 20215 yr On 18/06/2021 at 23:11, Thorfun said: https://www.ecowho.com/tools/r_value_to_u_value_calculator.php I tried this and then panicked because the Celotex didn’t give me the u value I need. However my architect checked and it came out achieving the u value. So just be careful using this webpage as it wasn’t accurate!
June 21, 20215 yr 56 minutes ago, John latimer said: I tried this and then panicked because the Celotex didn’t give me the u value I need. However my architect checked and it came out achieving the u value. So just be careful using this webpage as it wasn’t accurate! fair enough. it was one of the first hits on Google. I've not used it before. actually, seems to work ok for me from what I can tell. what r-value is the celotex? Edited June 21, 20215 yr by Thorfun
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