Great_scot_selfbuild

probably end up being about 30-40mm. Foundation is a suspended beam & block floor, DPM, 150mm PIR, Vapour membrane, UFH, slip membrane.

@torre The vapour membrane is below the pipes, the slip membrane on top.

We’re covering a small area of UFH (which was too shallow to lay the dry screed) with self levelling compound. In searching about SLC I’ve seen mention of a primer - is this always needed? The SLC will be onto a slip membrane which is over the pipes. This is the stuff I’ve been recommended to use.

Yes - this is what I’ve had proposed, but I’m taking it on myself now that I’ve accelerated up a steep learning curve!

@FarmerN sorry - what do you mean by ‘half run’?

@crispy_wafer thanks - we do like some of the more doable DIY and are in need of controlling the budget, so doing this is very much worth our time! I also think I am more focussed on tidy routing of services…

This feels a bit high - what’s the opinion here? Just before receiving this, I’ve been looking at running the pipework from plant room to the end points, then this came in (I’m now definitely considering running the pipework myself). Approximate scope: First fix plumbing pipework install. Only installing a mains connection point in the plant room (leaving the UFH / DHW / ASHP to others). 260sqm, 4 bed house with kitchen sink, dishwasher, freezer with water/ice dispenser, downstairs WC, washing machine, family bathroom & 2 en-suite. Doesn’t include bathroom installation (just pipes to the correct positions in the wall). Labour cost £2,750.00 for all pipe installation (not bathroom install) Materials cost £1,780.00 For all materials as above based on 28mm copper main to plank room plus fittings and stop cocks plus 22mm hep2o pipe and fittings for the hot and cold runs with 15mm hep 20 and 15mm copper spurs. Also, isolation valves to toilets, sinks, bath and showers. Thoughts? Experience elsewhere?

We’re approaching the point of having the plumbing first fix done and I’m not getting the confident feeling from our plumber - they’re asking for the design of the plant room and system configuration. It seems they are skilled as the practical work when told what to do, but now I’m looking into what a design should look like. I’m not expecting our principal designer to provide a design of the plumbing pipework, and although I’m looking at alternative plumbers, I now want to see some examples of what to expect as to a design / configuration of the plumbing pipework. If it’s not that complicated (which I don’t believe our system is) then in order to get a neat and tidy install that we’re after, I’m wanting to work out a design even if it’s just a means of me assessing whether the plumber we contract proposes something similar or miles off. Help me educate myself - TIA

@garrymartin Out of interest, how is this calculated? In terms of ‘enclosed in insulation’, I’ve just been thinking this over, how enclosed is enclosed (if this makes sense). Our situation: There will be 75mm batt insulation in the 89mm stud walls (3m high), then cables running above the insulation in the ceiling space (425mm deep posi joists, with 100mm acoustic insulation), and then out into the plant room.

Mandated in our planning conditions - seems to be a default on all planning approvals from our council (not sure if wider as they all seem to vary so much).

Couldn’t agree more. I’ve yet to find an element of this project where doing some due diligence and checking of my own hasn’t thrown up very valuable questions or even identified glaring errors. I equate it to doing a QA ‘dip check’ and then finding I quickly need to ramp up to a 100% check 😭

Part of the challenge - we haven't decided yet, but equally this could change in the future anyway, so I'm just looking to install the wiring to be the most robust / good design we can. If it future-proofed the design I'd even go for 10mm, but if this is HUGE overkill and only really needed for industrial systems, then I don't want to waste the money. Based on me searches, I'm inclined to run separate 6mm radials. I assume a double oven is one (not two) cable, and a warming drawer is another(?)

I'm looking to make sure we document our electrical design and detail of all the layout. I have a very useable and functional method I'm using at the moment, but would like to know what it 'should' look like. We have a principal designer and this detail is exactly what I expect to be provided, but I'll be honest - on some of the nitty gritty drawing detail like this, I think it may fall short of expectations. Hence, I'm interested in: 1. Is there a layout / standard style that an architect would produce (to be clear, our PD isn't an architect - we couldn't afford to use our architect from planning phase for the construction drawings). 2. Are there other methods that anyone has found to be preferable / useful / look good. Thanks

We're laying first fix wiring with our electrician but the only size cable we have on site (at the moment at least) is 1.5TE (light), 2.5TE (power) and 3CE (blinds). I've not yet seen any radial circuits for the key appliances that I would expect to have on a dedicated circuit. Having done some searching and ChatGPT (but never fully trusting it), responses come back referring to oven/hobs on a 6 or 10mm2 cable and appliances could be on a fuzed spur from a ring, but radial is preferred. I'd much rather have more robustness in our design for the sake of a small cost of some cable whilst all the walls are open. Looking for a second opinion from those who know about this stuff. Detail: Induction hob, cable run = 25m double oven & warming drawer, cable run = 30m TIA

How are people fitting their MVHR unit to the wall? I’ll be unboxing ours this weekend and hoping that there’s some instructions inside, but I’ve had no detail on installation from the company (yet - have emailed, but waiting on a reply).