How to Insulate a Pitched Ceiling (between and under rafters)

[@Sinchers]

delivery driver sounds like a real pro!!😂

[@oldtimer43]

The one thing I can guarantee is you won't regret the time you spend on insulating. I remember feeling the same way on my extension, I just wanted to get it done so I could get on with plaster boarding etc. However I now need very little heating to keep the place at the right temperature even on the coldest days in fact I split my underfloor heating into two separate areas in my living room and have never found the need to use the second one!

[@stevepettifer4896]

Count yourself lucky - part of my house is 200 year old cob and the rest is 20 year old extension. I have no access to the roof void in the new part and I'm certain that at best I have 50mm in the rafters on the sloped parts of the roof and 100mm mineral wool above the ceiling, and that ceiling is vaulted and 11-12 feet high. The windows are crappy old aluminium framed double glazing and they are hopeless at keeping heat in in the winter. We have wet underfloor heating run by a 6Kw electric flow boiler since we cannot have oil or LPG for various reasons. My energy bills are astronomical and the house is rarely above 18C in the winter unless I spend even more money. It may be a pain now, but you'll love it in winter! We used to rent a new build over the road, a big modern 4 bed detached house (with a cart lodge that had solar panels, oddly enough) and oil heating/hot water. It was so cheap to run because the insulation was outstanding: I think we spent about 10-20 quid a month on electric and an average of perhaps 40-50 quid a month on oil throughout the year and we weren't shy with the heating. There was a log burner and we only ever lit it because it looked nice, but it got so hot so quickly, it was crazy.

[@THE-AIDEN-PROJECT]

I've done a loft conversion with a similar build up of insulation like this and we didn't really need to have the heating on upstairs at all. As I've worked on the air tightness too I've actually undersized my heating set up for the cartlodge, hopefully I won't regret that decision! Your place sounds interesting, we was considering a big cob barn in Devon at one point. We passed on it though because although it was in a lovely scenic area the building was orientated the wrong way and the permission only allowed for North facing windows. We also let a holiday let investment go on the basis it had a boiler like yours and they tried to lie to us about the electric bills 😂 I recall they said £30 a month. It was grade 2 listed, solid walls, no insulation and single glazed windows.

[@stevepettifer4896]

@@THE-AIDEN-PROJECT 30 quid a month?? Ha ha!! We spend £167 a month, every single month of the year for just two of us and I could easily spend way more. And we're very fortunate to be locked into a very good tariff for the next year hopefully, otherwise by now we could easily be paying double that. I considered an ASHP like you're going to install, but I'm not sure we actually have an appropriate place to site it plus we need to replace various windows and doors to improve performance first (even if the RHI was going to continue, we'd have to do that to qualify but we won't make it now). I'll likely have mostly triple glazed units when money allows and then one day I guess a heat pump might be on the cards, but that depends on money since this is our first and hopefully only house so it cost us quite a bit and we had very little equity so the mortgage is not small. It's just a matter of time: Mostly doing repairs and replacements that previous owners couldn't be bothered to do or cheaped out on, will probably look to do the windows and patio doors in our bedroom (there's a small balcony) in 2023, and then do other groups of windows as funds allow. Hoping that next year's planned repairs etc aren't too pricey as then I might get a new back door as the existing one is utter trash, single glazed, badly fitting stable door with no threshold, so slugs in the kitchen are not uncommon. I do try and do what I can personally but I'm nowhere near your skill levels so I know my limits!!

[@THE-AIDEN-PROJECT]

@@stevepettifer4896 you can do more than you think you can 💪 half the time it's about confidence. That target date for me to qualify for the RHI is out the window now, unless I get 20 blokes in to help me 😂 I'll just have to suffer the full cost and save some money elsewhere

[@stevepettifer4896]

@@THE-AIDEN-PROJECT ah that sucks man. It makes a big difference for sure. I do do more than I ever thought I would and it gives me an excuse to buy tools (DeWalt!), but I'm basically a monkey with a hammer. Very basic electrics are ok but plumbing scares me because I'm terrified I'll bugger up any joint on copper that requires an olive or similar and that it'll leak forever!

[@THE-AIDEN-PROJECT]

@@stevepettifer4896 I prefer plumbing over electrics, a leak isn't gonna kill you 😬

[@northeastcorals]

Feel your pain, I've just spent best part of a week fitting 150mm board between rafters but each rafter has a collar bolted to it at the apex & 3 struts bolted to it at the bottom in the eves, which made fitting around all these shapes a complete nightmare. I'd have loved to just block off the eves like a lot of people do, which would have saved a load of work fitting insulation around all of the struts but I just couldn't bring my self waste that much storage space. Still got the over rafter boards to fit yet :(

[@THE-AIDEN-PROJECT]

haha it just feels relentless doesn't it! Luckily enough I had my mate do the between rafter bits whilst I tried my hand at some bricklaying. The over rafter boards go up quick in comparison though 👍

[@chrissimmons118]

Hey Aiden. How does that Ecotherm compare in price to the Celotex? I know it's all pricey stuff.

[@THE-AIDEN-PROJECT]

Back in the day ecotherm was cheaper but now they are pretty much the same price. I only got ecotherm for the 25mm stuff as that's what the builders merchants supplied, even though I could get the Celotex slightly cheaper elsewhere. It's just a matter of shopping around and hopefully finding anomalies in the market. Currently there's a place in London that's selling 25mm pir 30% cheaper than other firms (they will send either ecotherm or quintherm). Ecotherm is owned by Kingspan and yet Kingspan is the most expensive out of all of them. I can get cement 30% cheaper in London too. You would think London would be the place where materials cost more but it never seems that's the case 🤷‍♂️