Tetrarch

Wall Insulation - I'd agree that battening and/or 100mm wall insulaton would be best but this is really aesthetic with smallish windows to the original house that I can't change and the fireplace that I can recess a bit, but 100mm+ is just too much IMO. I can probably do 100mm on the upstairs North side as there are no windows on that aspect My general thoughts that if I go for high spec in the new parts ~(and a new roof) plus the MVHR that this will mitigate for my slightly sub-optimal efforts in the old part of the house Floor joists - Just an upstairs problem. Is this critical? There are no downstairs joists or voids

Solid Wall - Really good question......I was hoping to use the MVHR to control humidity/dew point. I've seen this on another thread on here - this post was really following up on that. Mains Wiring - The existing wiring ran under the floorboards. I have to either run mains wiring round the perimeter or drop down from the ceiling. My understanding is that if I use a purpose built aluminium channel as skirting board then that is allowable (unlike routing wooden skirting which is ostensibly not). There will of course be upwards tails to each of the sockets. I'm thinking of going "smart" so there may not be any lighting switches at all

Perimeter Upstand - There is a thin (10mm) blue insulation later between 80mm slab and solid wall. Diagram updated

See above

Underfloor Insulation - 100mm was to replace removed floor joists/floorboards. Definitely will insist on 150mm when digging out remainder of early 20th century and 1970 solid flooring - thank you VPC - diagram updated - apols Airtightedness - Not tested officially, but house seems relatively airtight. I will check this is as good as it can be as part of the MVHR install Regards Tet

Thank you so much for taking the time and trouble to reply. I have updated the images with some more detail/explanation below and will address comments/questions individually

I'm not sure if this belongs here or somewhere else as there are Insulation, electrical, ventilation, aesthetic and other considerations all rolled in. Below is the layout (subject to planning approval). You'll note that only about 1/3 of the downstairs external wall length is actually solid/original so my concerns about damp/dewpoints etc are here. Upstairs will be like this: and this my idea to remedy the uninsulated original 1914 building: The UFH is already done. Everything else is up for grabs. Some explanations/justifications/concerns here: MVHR - To maintain humidity control without trickle vents or airbricks Silicone Render - Open to other ideas 60mm Insulation - Balance between insulation and aesthetics Shadow Gap - No regular doors downstairs - going for super minimal finish Mains Wiring - Is this allowed? Hollow Skirting - Where can I source this? LVT - Amtico Spacia - Me and Mrs Tet agree, so that's sorted Any thoughts/criticisms/recommendations very welcome Regards Tet PS There are a couple of other windows - those on the floorplan are the full-height openings/glazing

I agree that ad hominem attacks on you are undesireable. I also agree that dismissing your entire argument because of a few personal inconsistencies and imperfections isn't appropriate. However, your "no right settings" comment is also both deliberately dismissive and too broad a generalisation and weakens your argument For urban areas you have a point, but from semi-rural to Scottish Highlands then their use can be acceptable, especially if no gas is available. I am a double-biomass user - Wood Pellets and a WBS. I have no access to gas and decided to ditch a decades-old oil boiler. I would be interested to know whether your critique of WBS extends to pellet boilers also? Regards Tet

Not a professional. I installed an 40sq m EPDM garage roof in 2003 with the full intention of covering it with protective gravel. I never got round to it and sold the house with a perfectly performing, fully intact roof covering last year. Since moving into our new place I had a small GRP roof professionally installed over a fireplace and have self-installed two EPDM roofs (one 30sq m and one 3 sq m). They are so easy to install and need no maintenance. Regards Tet

That's a great idea - thank you Tet

If all goes to plan we'll be having a new slate roof fitted and I'd like to have a solar array embedded in the south-facing portion of it. I've asked a couple of roofers (one by reference and one who lives three doors away) and neither have any solar roofing experience. Who should take the lead here? The solar company, or do I have to find an appropriately experienced roofer? Regards Tet

I'm planning on doing something similar but also with an MVHR - does this eliminate or mitigate the internal-to-external issues? Regards Tet

OK - now I'm confused... I've never heard the word "dwang" before so I went a-checking https://en.wikipedia.org/wiki/Dwang Here it's referred to as a "nogging" - I've always thought (and the above posts would tend to corroborate) that it is a noggin. Anyone come across this before or does Wiki need a correction? Regards Tet

Vote for Rubber for me I self-installed an L-shaped flat roof 20 years ago on my previous house (still going strong). Recently, I've installed rubber onto two outside buildings It's cheap, completely waterproof and easy to install, my only real criticism is that the flashing and finishing accessories are expensive. Regards Tet

I can see that my previous comment might easily be misinterpreted. Following your comments I will now be using glued 22mm chipboard with PW under the shower tray, cut to exact dimensions and appropriately noggined Thanks and regards Tet

Thank you both for your comments. I had assumed that becuase ply seemed to almost a requirement for the shower tray that it would be a superior product for the remainder of the floor. Is any filling required or even recommended for the joints prior to LVT or are they good enough as are? (You can tell that the previous experience really burns - 20 years of looking at an unremediable DIY mistake in a premium product) Regards Tet

I laid an Amtico floor about 20 years ago and whilst I was quite pleased with the outcome I did have a visible line across the bathroom where the plywood sheets were butt-joined I'm in a new house with a new bathroom planned, and whilst I now consider Amtico overpriced I'm looking to lay LVT again, but definitely with a T&G sub-floor of some sort. My thoughts are that 22mm T&G ply would be the bees-knees in terms of spec for the floor . The hierarchy is probably: A. 22mm T&G plywood B. 18mm T&G plywood? C. 22mm T&G chipboard? D. 18mm T&G chipboard Does anyone have any experience or recommendations that they would care to share? Regards Tet

IMO it is a valid complaint. I had the same from an old neighbour when I renovated a kitchen. I re-routed the vent via a rigid channel within the cavity wall and had the vent exit at the rear of the house, effectively adjacent to the boundary Regards Tet

Thank you for the replies. I chose the 15kw Biowin to replace a 1950's oil boiler in an area that is nor connected to the mains gas grid. We live in a rural setting and so I am sanguine about our contribution to pollution from our boiler, and indeed our wood burner. My intention is to go for a 300L Megaflo and run the boiler every other day. First things first will be fitting a water softener..... Regards Tet

I had a Winhager BioWin pellet boiler installed in December 21. At the time, pending a planning appeal we had it connected only to the upstairs rads and the UFH that has been installed so far. I am using an immersion heater for hot water and a basic 8.5kw electric shower. The heating is plumbed ready for HW delivery but it is not yet connected. The planning appeal is dragging on interminably so I'm now looking at potemtially another Autumn/Winter under these conditions. Knowing that the run cycle for the pellet boiler is fairly long I was thinking that a larger HW store with the HW run every other day would be more efficient than a small store/daily run when the heating is off during the summee. The question is how do I optimally size a megaflo (or similar - open to recommendations) to accommodate this kind of arrangement? Our household is just two persons so just a couple of showers and hot water for washing and washing up. Regards Tet

We have a pellet boiler for heat but I like the EV-as-a-battery idea. Regards Tet

Thanks guys - I am convinced. With energy proces going only one way and EV's an inevitibility, now is probably the right time to consider solar. Next consideration is yes/no on storage and to wait for planning permission so I can know how big my South-facing roof will actually be... Regards Tet

I'm definitely having a new slate roof installed over the next year or so. I'm also considering getting a solar array, but am not sure about the economics Is there any way to pre-fit a roof for a solar array at the time or is this one thing that sits between trades? What would the likely sunk cost of this kind of approach? Any advice, suggestions welcome Regards Tet

House is a 1914-built detached that is (PP pending) going to be extended and refurbed, including a complete external re-rendering and intternal re-plastering. The plan is to have UFH downstairs and rads upstairs fed mainly from an ASHP. Also, considering an MVHR to provide superior ventilation in a more sealed house The insulation is going to be substantially upgraded. From here https://www.thegreenage.co.uk/thickness-solid-wall-insulation-u-values-can-achieve/ it states a requirement to add 67mm of PIR to a solid wall to achieve a u-value of 0.3 My current thoughts are to add 25mm internal insulation using insulated plasterboard and 50mm outside on the old solid walls under a new render.This will avoid creating too much depth on the reveals but will improve the u-values to the right levels Any reason why this solution won't work? Regards Tet

Absoltely none. May I pop back to my original question. The Jablite (no particular reason for choosing this brand, are others better/cheaper?) comes in standard thicknesses up to 200mm. Listening to the previous comments; to accomodate any unevenness I was thinking of getting a 50mm layer to get a proper level and then laying the 200mm on top - does that seem a sensible plan? Do I need to tape the 50mm layer or just lay the 200mm at an offset and then tape that Finally, the Jablite 70 would seem to suffice - is there any tangible benefit from upping the spec to the Jablite 100? Regards Tet