lookseehear

You could eat your dinner off that!

This is what I always do. Have a good jump on it myself and know that the kids at 1/4 of that will be no problem.

I've done something similar in the kids playroom and screwed 3x2 to the ceiling joists running perpendicular, then some little stainless brackets with 4 screws on each into the 3x2s. The stainless ones you linked look like they would be absolutely fine as long as the correct size hole is drilled.

'Fluffy stuff' as my builder calls it is going in. Seems pretty easy to work with. And here's the jig for cutting the cavity tray profile. Straight cuts are super straightforward, but on an angle it's a lot trickier to hold the line.

I came up with a solution for this today. I bought a couple of packs of these driveway grids https://www.wickes.co.uk/Wickes-Ground-Grid-Base---100-x-100cm/p/236266? which are 250x250 and come in a pack of 4. They cut really easily with a track saw, so I've cut them into roughly 120mm wide strips. Should do the job nicely.

Firstly - welcome to the forum and sorry to hear all the issues you've been having. Old houses are a bit of an enigma in terms of damp. Some will be fine when you expect them to be damp and some damp where it doesn't make sense. In general it's probably good to start by making sure you've covered the basics. Are all gutters and other RWG in good repair? Any high external ground levels? Ventilation it sounds like you have covered It seems like the work you have had done is all to contain water within already wet walls by tanking and re-rendering with highly waterproof products (I'd be highly suspicious of the lime they said was used in the render - throwing in a bag of lime hydrate into a cement render doesn't make it a lime render). The pointing looks like standard cement pointing to me as wel. Wet, uninsulated walls will generally be cold in winter because wet walls require so much more energy to heat than dry walls and are much worse at insulating than dry walls. This means that even if the moisture within the walls is contained via tanking, you're much more likely to get mould and damp spots in corners because you have cold walls in areas that are hard to ventilate. I highly suspect that the walls being wet all the time is bad for their general structure over time, and can lead to joist ends rotting, but that seems to be the direction the damp proofing industry has gone because it's easy to hack off what's there, stick a load of tanking stuff on the walls and charge a lot for sorting it out. The 'heritage' approach would be to repoint all the walls with a lime putty based mortar, remove the tanking products and plaster with a lime putty (non-hydraulic) based plaster. These are time consuming tasks because they can be seasonal (you can't use lime putty mortar in winter) and take a long time to set in the right conditions (days to weeks). It's also hard to find tradespeople who do this and do it well for a reasonable price, so a lot of people learn to DIY it. How attached are you to the house? It looks like quite a lot of disruptive work to make it right in any case.

Would you expect the batts to stay in with friction alone? In one section there's enough cavity below floor insulation level to have a gap, but too low for there to be any ties to sit the batts on. I'm tempted to buy some little plastic plant pots or something to put in the bottom of the cavity for the batts to sit on. For the other section of wall, the batts need to go pretty much right down to the base of the cavity. Does it make sense to stand them off the bottom 25mm or so, so that they could drain if water did get in, and so they can't wick moisture up from sitting on damp concrete? Again, are there products to use here? I looked on Knauf's website which seems to have no technical advice.

Our builder seems to be very keen on squirty expanding foam (he keeps talking about all the areas he likes to use it). I have heard not great stuff (it can sag, it can be used to fill bigger gaps than it should really be, it can be a lazy way to get something done etc etc). Is there a general concensus or guidance anywhere about where the appropriate uses for it are? I'm guessing between sheets of PIR is probably a good place because it's probably a similar type of material and the gaps should be small if the PIR has been cut properly. Anywhere that it often gets used that it really shouldn't? Also any brands to look for or avoid in particular?

This is so so helpful - thank you!

Just wondered if anyone had any insight here, thanks in advance!

As someone who is just about to trust his builder to install full-fill batts, can anyone provide practical advice? My builder is skeptical about the whole thing. We've got a roll of knauf loft roll knocking about which he's been using to insulate some pipes temporarily until they get moved, and he keeps saying to me that the loft roll and the cavity batts are basically the same thing and showing me a wet piece of loft roll which got wet and now resembles something the cat dragged in. My specific questions are: Do you fill right down to the bottom of the cavity or leave a small gap at the bottom to avoid moisture wicking up? If using cavity trays, should the batts be packed below and above in contact with the trays or a gap left? How well does it need to be protected while block-laying? It's guaranteed that we'll see bad weather while the walls go up. I assume just a layer of DPC to keep an area dry. What about actually installing it in the wet? Anything to note with wall ties or junctions with existing walls? I assume you air on the side of overfilling vs underfilling, ie slightly compress the insulation into place? Reading through this thread, I'm wondering whether EPS beads are more foolproof. What about the fire performance though? U value in a 150mm cavity looks v similar to Knauf Dritherm 32.

Not an expert, but I would be a little wary of IR camera results from window panes themselves. Glass will allow IR radiation through, so it's possible you're measuring the temperature of what is outside when measuring from inside, or what's inside when measured from outside which will distort your view of the windows. As has been said before, if your glazing isn't blown and is generally in a good state of repair, you can find out what the u value is roughly and therefore what is to be gained by replacing them. Thermal cameras are better for identifying cold bridging around the windows, unseen draughts and the overall performance of the frames than the window panes themselves.

I've been looking more into this after taking some plaster and old newtonite off the walls at home. As expected the stone is pretty uneven, but looks pretty dry. This is about 2 feet above the ground. I'm thinking about making up my own base layer of lime plaster as a levelling and airtight coat, rather than a cement based parge coat. I was thinking that a 3:1 mix of sharp sand and lime putty (slaked quicklime) with some synthetic hair added is probably the 'best' thing for the walls. I assume this would suffice from an airtightness perspective and would likely be cheaper than bagged alternatives like Baumit and better than a cement based parge from a drying and wall-health perspective. If I'm only using this to roughly level, hopefully I can get it done in one coat and it won't have to be particularly neat. Over this I'd do the aformentioned wood fibre or mineral wool with ~50mm battens or a 63mm CLS stud wall creating a service cavity, then plasterboard and skim. If the plasterboard turns out to be problematic down the line, it would be possible to swap these out for a wood fibre board with lime skim, but I'd hope not to have to do this obviously! Window reveals would also be lime plastered, then lined either with some PIR or somthing like Bosig Phonotherm (https://www.ecologicalbuildingsystems.com/product/phonotherm) or maybe a wood fibre reveal board. Any thoughts on the above? If the lime putty based plaster is sufficiently airtight I wouldn't bother with an intello membrane, and instead would focus on getting the details of the lime plaster and taping to joists/floors etc right.

Does this mean that Intello type membranes are not worth the cost? Should we be looking at cheaper alternatives instead? I've always had a nagging doubt about gore-tex in outdoor clothing. Wearing it while cycling leaves me similarly sweaty to wearing a standard waterproof.

That at least should offer you some comfort - less of a discussion about how you think it should be done vs how the contractor does, but a simple failure to follow the agreed plans. I hope it doesn't set you back too much time-wise.

This is the hard bit though - when do you actually commit to something? Or do you just reconcile yourself that you'll learn more after you've committed and just have to make the best of what you've already committed to?

Good point! I suspect the hob will be on an island though so we'll likely have an extractor above. I'll have another look at what's available when we come to spec the kitchen fully, but I just want flexibility in terms of pan size and position. I've got a 14" round cast iron crepe pan which I've not been able to use since we've had induction. It worked great on our old electric aga but the electricity bill was eye watering.

We've been induction converts for a while. A place we used to holiday at in Sennen Cove had one in the late 90s - didn't see another for a good number of years but they're all over the place now. When we get the kitchen redone, our treat to ourselves will be one of these https://www.miele.co.uk/product/11144100/induction-hob-with-onset-controls-km-7678-fl-black.

I think although dot and dab can be unpopular, in this case your risks are likely fairly low. You've only got 25mm PIR, so most of your insulation is within the cavity. This means that while you have a gap between IWI and blockwork, that inner skin of blockwork is on the warm side of the CWI and therefore shouldn't go below dew point and cause condensation ordinarily. The parge coat should hopefully reduce risks further by making the blockwork somewhat airtight, meaning that air flow from living spaces into through small gaps into any void behind should be minimal.

Another option which has been discussed quite a bit on the forum is a thin stud wall fixed at floor and ceiling level. You then have the option of insulating between the studs with a wood fibre or mineral wool insulation. You can attach plasterboard to the studs and skim over the top. I completely echo your sentiment around the "I wouldn't have done it like that" you get from tradespeople. We have a builder who is constructing an extension then will help us with the renovation works to the existing house. He was building a retaining wall for the garden, but when we had a groundworker come over with a digger to shift our giant pile of clay from excavating the foundations he kept saying to me "why's he done it like that, that isn't how it should be done". We have to have some element of trust in the tradespeople we bring in, or we have to understand every detail to be able to tell them exactly how we want it to be done.

I thought you could only ewi a cavity wall if the cavity was either filled (eg with EPS beads) or sealed, otherwise you end up with a well insulated outer leaf and a cold cavity.

We have the Drayton system. 7 or 8 smart TRVs, 4 room thermostats. I wouldn't buy again. We needed three of the range extenders to get to all TRVs and even then some are a little low on range and I get the occasional disconnection notification. The reason it works for us now is that our house is so poorly insulated it means we can warm the rooms we're using, not the whole house, and we can avoid having any rooms too warm (19 is a treat for us - typically rooms are set to 17 and 18 or 18.5 if being occupied). When we have a better insulated, more airtight house I would have regular TRVs and try to size radiators to the room rather than try to zone too much, as I understand in general it isn't a very efficient way of heating. I also hate having to go round replacing batteries. I assumed I'd be able to use rechargeables but they only last half as long before the battery warnings start pinging. I won't buy any smart home products with batteries in future, it only adds to the faff. I also want to avoid anything needing range extenders because reliability just isn't good enough at this point.

Copy/Paste from ChatGPT - no guarantee that it's correct, but I find this is the kind of thing it's pretty good at: Here's a breakdown of your questions with answers based on VAT regulations and property tax rules in the UK. However, always consult a tax advisor or HMRC directly for confirmation specific to your circumstances. 1. Does the 5% VAT rate apply to limited companies, not just individuals? Yes, the 5% reduced VAT rate for eligible construction work applies to both individuals and businesses, including limited companies. The eligibility is based on the nature of the work and the property, not the entity undertaking it. 2. If my limited company registers for VAT, can it avoid the VAT charge altogether? If your company is VAT-registered, you can claim back VAT paid on expenses related to your business activities, including construction costs. For qualifying conversion projects, the builder should charge 5% VAT on eligible works, and your company could then reclaim this 5% VAT as input tax if the property is used for taxable supplies (e.g., renting or holiday lets, which are considered taxable supplies). If the property is used for non-taxable purposes (e.g., private residential use), you may not be able to reclaim VAT. 3. Are there restrictions on the sale of the property after claiming the reduced rate? The 5% reduced rate applies to the construction services, not to the property itself. Selling the property does not retroactively affect the reduced rate applied to the construction. If the property is sold as a new residential dwelling (within 3 years of completion), the sale may qualify as zero-rated for VAT purposes, which can be beneficial for VAT recovery. 4. Are there restrictions on the use of the property after claiming the reduced rate, for example, short holiday lets? The 5% VAT rate on eligible works does not impose restrictions on the use of the property. However, the subsequent use of the property (e.g., for holiday lets, long-term rental, or personal use) will determine your VAT obligations. Holiday lets are treated as taxable supplies, allowing VAT recovery on associated expenses. Personal use or standard residential rental would not typically allow for VAT recovery. 5. Since I'm just making up a certificate and handing it to the builder, how does HMRC know I'm not evading tax? Is the builder accountable once he's accepted my certificate? The Certificate: The reduced rate applies to certain types of conversions (e.g., converting non-residential to residential). HMRC requires you to provide the builder with a valid certificate to substantiate eligibility for the reduced rate. Builder Accountability: The builder is partially accountable. If HMRC later deems the reduced rate incorrectly applied, they could hold the builder responsible unless they can show they acted in good faith based on your certificate. Your Responsibility: As the issuer of the certificate, you are also responsible for ensuring the accuracy of your claim. HMRC could challenge the claim and impose penalties if the reduced rate was not genuinely applicable. Recommendations: Drafting the Certificate: Follow the template provided in VAT Notice 708, Section 18.2, and ensure the property meets the eligibility criteria. Professional Advice: Engage a VAT consultant or tax advisor to ensure compliance and clarify your eligibility for the 5% rate. VAT Registration: Consider registering your company for VAT if the property will be used for taxable activities like holiday lets. This could improve your VAT recovery position. Documentation: Maintain clear records of the property's usage and the justification for the reduced rate.

Shouldn't there be some consideration for the carbon implications of demolish and rebuild? It's difficult for the average person to quantify but it definitely was a factor when we looked at this. There's some legitimacy to the idea that you shouldn't knock down a structure that is otherwise sound. It isn't always all about the pounds and pence, particularly given there's uncertainty whatever route you go down.

Not that I can see. I think I'm just going to give up on trying to find medium density blocks for a sensible price that can deliver and go with the standard dense at £1.25 each.