MortarThePoint

I think I recall someone saying somewhere that they had glued their toilet to the screed rather than bolting it down. This is of interest to me for two reasons: Allows UFH pipes to pass below. In one place I haven't finalised the toilet position Safer over any membranes If glued down, is there any way of getting the toilet unstuck without smashing it if you need to remove it later?

Thanks Markc, Can you recommend a glue for metal Frame? I was worried that the smallest amount of water would cause the galvanising to whiten and I think I recall it being pretty easy to pull that off.

Do you think this would work with a metal frame partition?

Some photos. In the one from above you can just see a line 450mm from the side wall and a second 450mm from the top wall. They mark the edges of the currently proposed UFH layout (green in previous post). The second photo shows a pen X on the wall which is in-line with the waste of the toilet the other side of the wall.

I know all of these sorts of things should be worked out way in advance but... I am struggling with the placement of the loo in our ensuite. There are a few pipes that need to converge to then pass through the concrete slab floor (first floor). 2no. 100mm toilet pipes and 1no. 40mm shower waste. The overall size of the ensuite if 3000mm x 2450mm. The ensuite layout basically comes down to two options shown below. I am laying the UFH (water based) and need to finalise the position as to keep both options alive but than risks cold feet whilst sat on the loo. I can't get the UFH pipes to close too the area where the toilet mounting screws will go as that's a recipe for disaster. I have shown the current UFH planned area in green in the layouts below. I don't think I can extend the pipes to create an area to heat the right foot in the second layout due to the mounting holes of the toilet. I think the second layout would need a T-junction mounted on the rear of the ensuite toilet (see image below of what going in where) and there would be a minor heights issue as the other toilet's waste will need to have dropped due to pipe fall, but I think that's only within tolerance though so should be fine. I'm not sure how I would join the shower waste that's coming through the wall though. I could just send it through the hole in the floor and join lower down which is where the ensuite shower and bath wastes will be joining having passed through their own holes in the floor. I may have to have push the loo away from the wall and have a box that goes as high as the top of the ensuite toilet cisten to buy some space (?) Holes quite forward: https://www.victorianplumbing.co.uk/burlington-close-coupled-wc-ceramic-lever-flush-bur-p5c1 Holes towards the back, perhaps 300mm forward of wall: https://www.victorianplumbing.co.uk/melbourne-ceramic-wc-pan-cistern RED: 110mm soil pipe coming from toilet mounted on other side of wall so at it's exit height. BLUE: 40mm shower waste pipe coming through the wall at a height of "in the screed".

This is Libra: https://www.abcdepot.co.uk/libra-resilient-bar-3000mm.html I bought 100 lengths so that may have helped.

Have a look at abcdepot, but I got it from Travis Perkins

Cool. How did you do joins in the membrane?

@joe90 did you just use duct tape to secure your membrane to the perimeter insulation skirt?

That's right, we certainly have an eye for detail on the things we are aware of. Just to double check, I am just using standard Cloth Duct Tape to tape my edges of the 125um membrane to the perimeter insulation skirt and any joints. I presume that's OK. I am planning to use a liquid screed (either anhydrite of cement based).

Wunda have done an excellent spiral design, so clearly either use different software or a particularly diligent designer.

If you want to fully nerd out on all of this you can check out IR761: https://www.jhbrandt.net/wp-content/uploads/2014/11/ir761.pdf A lot of the other sources of information for timber vs metal frame is subject to conflict of interest as the plasterboard manufacturers produce metal frames. I'm no saying they tell porkies, but there may be a configuration missing. Page 21 (not sheet, page) of IR761 has "Wood studs – 1 layer gypsum board" - STC 34 (90mm studs) Page 28 of IR761 has "Steel studs studs – 1 layer gypsum board" - STC 36 (these are 65mm studs though) Looking through the document can turn in to an amazing game of spot the difference (e.g. page 28 vs page 29) I don't readily see timber studs at 610mm c/c. Basically it looks like if you start from 65mm steel studs at 406 c/c with 13mm plasterboard each side giving around STC 35: Changing 406 c/c to 610 c/c adds about 5 Changing 65mm MF to 90mm MF adds about 5 Changing 13mm to 16mm plasterboard adds about 5 Doubling up plasterboard adds about 5 Adding resilient channel one side adds about 7 (not shown with 610 c/c studs though??) It definitely looks like you can have the insulation too dense (page 46 vs 40)! Some highlights: Page 89: 610 c/c, 90 steel studs, 16mm plasterboard lower density insulation STC 50. Page 93: 610 c/c, 65 steel studs, 13mm plasterboard (double on one side) lower density insulation STC 51. Page 120: 610 c/c, 90 steel studs, 16mm plasterboard (+13mm on one side) lower density insulation STC 55. Page 124: 610 c/c, 65 steel studs. two layers of 13mm plasterboard each side, lower density insulation STC 55. Page 245: 406 c/c, 90 steel studs, two layers of 13mm plasterboard each side, low/medium density insulation STC 60. Page 350: Double timber wall, 610c/c, double layers of 16mm plasterboard, lower density insulation STC 69. Good below 125Hz (e.g. 26.7 @ 50Hz) It's much harder to achieve good performance at lower frequencies (<125Hz). Of interest: Music: Spectrograms are a useful way of seeing the frequency distribution (and as an aside are good for AI like Alexa), Country music may be the worst in more ways than one as it turns out [link]. 'Subs' and 'Kick' are likely to be the most challenging [link] [another link] Snoring: "The fundamental snoring sound frequencies of the tonsil, tongue base, and larynx were approximately 330 Hz, 1000 Hz, and 652 Hz, respectively" [link] Farts: "The data show that most farts predominantly have power in sound frequencies between 200 and 400 Hz" [link ?] Films: Psycho (shrill music and women screaming) probably easier to cope with (if you're not watching it) than Jurassic Park, keep it down T-rex! The insulation side of it is really interesting. Rockwool would have you believe in the acoustic benefits of their denser insulation which doesn't fit the data. Insulation G1 is good and has a density of around 12kg/m3 and air resistivity of ~4000 mks rayls/m (whatever they are).

Playing with LoopCAD and the "Spiral Counterflow" circuit layout setting. It only uses one circuit, whereas for the "Single Serpentine" it allows you to set how many and for the first room I am designing it defaults to 2. That's a nuisance as I'll have to manually divide each room that has more than one circuit and hope to get the areas balanced. Not too bad (see third image) though need to factor in the feed from the door (adds about 2*3m) as It doesn't work to have a narrow pan handle on the area. I haven't balanced the lengths very well below as, once I have added the feeds, they will be about 86m and 92m. That's not too bad, balanced to within 10%.

Staples are cheap as chips. Not chips of wood coated in glue and squished together to form OSB3 though, they're really expensive.

Castellated panels aren't cheap of course. About 6x as expensive as clip track. Are you figuring the trays will protect the insulation from the screed and therefore no need for the polythene. That may be a risky assumption, what do others think?

If you've ever been in any doubt, I do make this stuff up as I go along ? I do think it's useful though. There's a window with a U-value of 1.2 and an area of 1m2. "£3 per U per m2 per year". That window is costing me £3.60 of lost heat per year. Windows are a bad example as they can create drafts as they are so heat leaky. How much heat lost through that bit of loft. U-value of 0.11 area of 15m2. "£3 per U per m2 per year". That loft is costing me 0.11*15*3=£4.95 of lost heat per year.

For my scenario* I can multiply a surface's U value by £2.85 and it will give me the annual cost of heat lost. Example, U=0.13 --> 0.13*£2.85 = £0.37 p.a./m2. Or dU = 0.01 --> 0.01*£2.85 = 3p p.a./m2 Quite handy for me to remember "£3 per U per m2 per year" [I know there's no such thing as 'a U' but it's a way of remembering it] 183days * 24h/day * 13K * £0.05/kWh = £2.85 [careful swapping between kW and W of course] * My scenario is dT = 13 Celsius, 6 months and an ASHP with adjusted COP of 300%.

I didn't realise how cheap Gas is and that makes the number lower still. It seems Gas costs around £0.03/kWh [1] so that marginal rate becomes closer to 2p p.a./m2 saving. Prices can change of course, but that would need a whole lot of change. https://www.ukpower.co.uk/home_energy/tariffs-per-unit-kwh I secretly hope someone points out I've missed a factor of 10 or something because spending an extra £5/m2 to improve the U-value by 0.01W/m2K is so far from being financially sensible (payback >150 years). Even knowing this, I find myself irresistibly drawn to improving U-values. Even the embodied carbon side of increased insulation is very debateable with decades of payback time, but that's another story.

That's right. The raw maths is: Heat Flow Q = U*A*dT Heat Loss E_heat = time*average_heat_flow = (days*24hours/day) * U * A * (Average_dT) For me average dT across 6 month 'heating season' is 13K (i.e. 13 Celsius) --> E_heat = (183days/yr * 24hours/day) * 0.13W/m2K * 1m2 * 13K = 7422Wh/yr = 7.4kWh/yr per m2. That is heat energy, to understand what I'll pay, I need to know how much heat costs me. Using an ASHP with a COP of 300% (reasonable) and an electricity rate of £0.15/kWh electricity, I can calculated that heat costs £0.15 / 300% = £0.05/kWh heat. 7.4kWh * £0.05/kWh = £0.37/yr per m2. It's all linear with U so to work out differences you can just scale that figure, so if the difference is 0.01 then the cost difference is (0.01 / 0.13) = 1/13 of £0.37/yr /m2. When I work this sort of thing out I keep thinking I am making a mistake, but it's how it works (at least for marginally changes on a good base figure).

Don' want to draw too much attention to this consideration as I know people's priorities are many and varied. In part it was a note for my own consideration of the pros and cons. Anyway, I made a mistake in the first sentence as it was supposed to be "Improving a U=0.13 area by 0.01 saves approximately 3p/m2/yr with an air source heat pump." The mistake is obvious looking at the next sentence, but I wanted to correct that. so: Improving a U=0.13 area by 0.01 saves approximately 3p/m2/yr with an air source heat pump. [dT=13C, U=0.13, 6mo-->7.4kWh/m2, E=£0.05/kWh --> £0.37p.a./m2]

2no. 100mm Omnifit Slab 35? That make up should be good and warm. R_ins=9.0. Is that targeting U=0.14?

I have 222mm rafters and need to leave an approx. 50mm air gap so was planning to use 175mm of insulation between the rafters and 75mm under the rafters (all Mineral wool). Here are some example build ups: 75+100+75mm Rafter Roll 32, R=7.81 cost £35.75/m2 90+90mm FrameTherm 32 and 75mm Rockwool 38, R=5.63+1.97=7.6 cost £21.09/m2 [NB: RockWool not Formaldehyde free] 180+70mm Rockwool Flexi 35/38, R=5.14+1.84=6.98 cost £12.23/m2 [NB: RockWool not Formaldehyde free] 90+90+90mm OmniFit Slab 35, R=7.71 cost £12.15/m2 90+90mm OmniFit Slab 35 and 75mm DriTherm 32, R=5.14+2.34=7.48 cost ~£14/m2 90+90mm OmniFit Slab 35 and 60mm PavaTherm 38, R=5.14+1.58=6.72 cost ~£16.50/m2 90+90mm OmniFit Slab 35 and 50mm EcoTherm PIR 22, R=5.14+2.27=7.41 cost ~£14.60/m2 120+50mm EcoTherm PIR 22, R=7.73 cost ~£22/m2 If I were to do it again I would 100% use counter battens outside the roofing membrane and fill the rafters. Improving a U=1.3 area by 0.1 saves approximately 3p/m2/yr with an air source heat pump. [dT=13C, U=0.13, 6mo-->7.4kWh/m2, E=£0.05/kWh --> £0.37p.a./m2]

For the garage, BG FireLine MR was hard to source so I went with GTEC Fire MR from abcdepot. The 15mm GTEC product has the advantage of being 2400 sheets rather than 3000mm. Whilst sourcing that I got confirmation from BG and Siniat (GTEC) that their standard moisture resistant plasterboard can be considered in the same way as their standard WallBoard when it comes to fire considerations, in theory. Untested though, but those statements were suffice for my BCO.

Duraline does appear to be available despite the BG website indicating otherwise at some point. Duraline: "Designed to provide enhanced sound, fire and impact resistance" 15mm only, 13.9kg/m2, TE only, 1200 x 2400/300 So almost as high area density as Soundbloc F (14.1kg/m2) but adds impact resistance. I've been quoted 1.2% cheaper than Soundbloc F. (~£14+VAT/sheet). As such, pit probably makes a better choice for walls though consider Habito instead for fixability. What to use under rafters in an attic is interesting as you probably want some impact protection, but ideally not the weight.

Ordered the TradeLine one at £2.35 per 3m length which is cheaper than 100x22 timber