MikeGrahamT21

Definitely needs BC, and be careful as if you renovate a certain amount, you have to do your entire property to current standards, which includes electrics and everything else. PP only required if you are changing the look of the building, if its going to look the same, then no PP required.

For the small amount i've done in EPS (13m2), i'm happy as it is, there is nothing over doorways anyway, so the drip effect isn't an issue, but for any future projects I think i'd lean toward rockwool, even though its not as thermally efficient, there is the added benefits of fire resistance and sound reduction.

Yeah thats right, i've had a sample from EWI pro of both the EPS and Rockwool systems, and when complete there is no different to toughness. The slabs are called duo-density. Yes the non-combustability is appealing, though i tried to set fire to EPS system too, and it just melted, PIR on the other hand does set alight and burn, until it carbonises.

Well, we finally made it, 3 years from when i first started! Just got some blinds to go up at the windows which haven't come yet, but otherwise done and dusted. Just wanted to say thank you for all your help, both from this forum and ebuild (thats how long its taken me lol!) The room itself is performing as expected, with an average temperature of 21C and humidity of between 40 and 50% (with hardly any ventilation at present, just the vents in the roof windows). The radiators I put in were massively over-specced, but at the time it was hard to imagine the room being easy to warm, indeed the calcs were correct and they rarely come on, even on the coldest of days, though it hasn't had its true test yet, but overall really pleased with this.

Yeah thats potentially the main issue here, i'd have to put planning permission in for anything other than brick finish (we would use resin brick slips like i used on the rear extension), ideally i'd prefer timber or a timber and render combo, I think we'd get it, just a lot of hassle getting there, plus we don't get on with our neighbours which helps greatly lol. What would you do for fire breaks in larsen truss? With EPS you have to have a rockwool section between floors, and though technically we don't have another floor, we do have a large uninhabited loft. Also what is the minimum depth of this system? I was thinking of using 100mm insulation (EPS/Rockwool) in the usual EWI fashion. Next year I plan to renovate the main bedroom, rip up the floor, replace all of our woodwormed timber, and replace, insulate and airtight, and then monitor the heat loss. This room has the largest area of unfilled party wall cavity, which potentially is the main source of heat loss in this room once the floor is done, but there is a chance we may not even require EWI if the heat loss is acceptable. I've been very pleased with the performance of the small bedroom which has had the above done, with no EWI (external wall makeup is approx 0.5U).

I was thinking simple timber, this look very similar to those i-joists but with gaps along, so yeah the thermal bridge side of things should be smaller, but still worse than EPS overall, and would be a more expensive system to install since you'd have a requirement for a render carrier wouldn't you?

Yeah I remember a house round here having that done a good 15 years ago, must have been EWI version 1, but I'm guessing the timber will be a massive thermal bridge, so probably not really worth the effort. Yeah the breathability side of things is very debatable, I remember running a WUFI simulation to compare between EPS and Rockwool systems, and the Rockwool system did actually give a condensation risk within its first few years following installation, due to its ability to absorb moisture, something which EPS doesn't really do. EPS is the obvious choice, and indeed the simulations i've run show no risk what so ever, but everywhere you look it says lime anything should remain fully breathable, and i'm not sure EPS would class as that.

Has anyone ever DIY'd rockwool EWI? The older parts of our property which are suitable for this are block and brick cavity (70mm filled with wool), but the mortar is lime based, so I'm keen to keep everything fully breathable, but wondered how easy it was to render rockwool in comparison to EPS? I did EPS on a newer part of the house a few years ago and found it easy to do. I also wonder about Rockwool's ability to cope with some rain on it before it gets rendered, since the elevation to be covered is quite large, it would likely take me a few weeks to complete, perhaps scaffolding with some form of cover on it to protect it from lots of rain?

Yeah an EWI wrap around is another option if you are going down that route, i'm still undecided on EWI due to cost.

I'd be interested to know the reasons why people say not to move it further in. The idea is to have the window form part of the insulation layer as i'm sure you know, if its mounted only an inch in from outside, you will always get some of the outer layer masonry showing through on the inside. Not sure if you have one, but this is easily measured with an IR non-contact thermometer, and as every building differs, you may be able to move it less, but choose a very cold day, with the heating on inside, i was amazed how moving ours in 5cm would make such a difference, the temperature gradient is very steep. Other option is to build an outer 'frame' to surround the window and brickwork for a small area, and put some 20mm PIR inside it, then clad with something which looks really nice

I would say definitely the main cause is the glass, perhaps consider changing the glazing unit for the highest spec double with warm edge spacers you can get, or you may be able to change the beading and fit a 36mm triple in (depending on the frame make). Another thing which I have found on our windows, is where they are located in the wall build up. I've found if they are an inch in from the edge of the external brick, our frames are a full 7-8 degrees colder than the ones which are set in around 2.5inch, basically like they used to do in the olden days when people weren't too bothered about deep sills.

Yes I spent a lot of time taping the cavity closers to the block work, and also taping all of the holes in the lintels, so that is covered. Also had a lot of fun filling a box lintel with expanding foam. I really think we are going to be many years before we actually get to the MVHR stage, i've 1 newly built room which needs everything taking off and starting again, and another 2 existing rooms, one of which needs taking back to brick, the other which just needs the floor doing (which i'm doing next year). I've placed an order for some Tado radiator thermostats, which individually graph temperature gain and loss per thermostat, i'm hoping to see in plain view, which rooms are done and which aren't. I do sometimes question why i'm going to all this effort when our gas bills are £20 a month, and we are in the house almost constantly. The rooms i have done, do have an unmistakable 'comfortable' feeling about them though, so I still think its worth the effort. I'm really looking forward to MVHR, and i'm certain it will be worth all this effort.

I've found a lot which has the ridging on both the outside and inside, which I'll definitely be staying away from, don't mind paying a little more for a smooth internal bore, and then a couple of manifolds.

Planning on using the 75mm flexible ducting, but trying to find some with a smooth internal bore to reduce noise and any dust collecting. Will plan where the outlets will be, but they are all accessible from the loft space, and will be completed when we decide what we are doing dormer wise, i've a feeling we probably won't do a dormer, in which case everything is getting lifted in the loft, cleaned, re-wired and loft legs putting in to get 300mm insulation in, and the ducting will go in at that point and be buried in the insulation.

We have a couple of hairline cracks in the living room ceiling plaster, not sure how we will tackle those without some form of messy filler which will then need sanding, I have seen a couple of paint products which claim to fill hairline cracks, maybe they would be better as an undercoat layer. Definitely plan on sealing the switch and socket outlets, i can see those as a major air leak source too, since no rubber seals existed in the 1960s.

Yeah I asked him about that a while ago, i've got all the parts on my watch list on ebay ?

These are all foamed up, but the AVCL sits above this anyway, directly under the floorboards, so shouldn't affect airflow into the room. I was going to go down the route of plastering round them, and then taping, but didn't have the time in the end.

Yeah the loft is prime candidate for all of the pipe work and the unit for sure, though we are toying with the idea of a single dormer, so we won't be doing anything like this until we've made a decision on that, but there will still be room either way. All of the windows i'm ordering have no built in ventilation, and I'm trying to get products which have zero or little leakage, using seals like QLon which are far better than their EPDM counter parts. I think I may rig up a blower door once we have as much done as possible, just to catch anything i've overlooked. Our main issue at the moment is the new kitchen which we had built 6 years ago, the plasterer dotted and dabbed, no parge coat and no adhesive round the edges, plus its still not signed off with BC as the electrician did a runner before doing the certs, so I've a feeling i'm going to have to remove everything and start again, and since i'm happy with plastering myself these days, i'll do it the proper way and get bonding coat and a skim on there, which will resolve that. Well as long as i'm on the right tracks, i'm happy with that, just didn't want to do all of this, and then someone say, you should have done x y and z whilst you were at it lol

Well that is my intention, just dont want to miss any tricks thats all whilst floors are up and work is being done. I would hate to spend thousands on an MVHR system to find its making matters worse.

Hi, I'm planning on having an MVHR system at some point in the future, and the bungalow we live in we are renovating room by room. I've seen for MVHR to be really effective anything below 3ACH is required, which seems reasonable, but how achievable is this? Our bungalow has suspended timber floor which I am fully insulating, and then laying an AVCL above the joists, under the floorboards which laps up onto the walls and is getting taped on. The walls are wet plastered without cracks, thickness approx an inch in total. Ceilings are double boarded, both layers plastered. I've sealed up ceiling light wire holes, and intend on doing the same inside the electrical sockets. Paying close attention to the windows and doors in terms of airtightness levels too, getting the best ones i can and the frames are getting taped onto the walls, with foam around the frame as normal. With this approach, what sort of airtightness level would I likely achieve? And if its above 3ACH, what additional measures would I need to take? I appreciate its difficult to guess with all this stuff, and I suppose an air test with smoke pen (or a self air test using a fan in a piece of ply) would be a good way to find anything i've missed.

Updated photos as promised. The light fittings are lower than their final position, i've had to put the step ladders underneath them as I keep banging my head! lol Grey one is going to get put on a hook to move it nearer the radiator wall, and the other just needs shortening, i made it longer so that my wife couldn't say can you make it a bit longer, covering all bases and all. Big pile of wood flooring will hopefully be down very soon!

I've never had any trouble fixing to OSB, maybe not as good as ply, but certainly not a problem

Ok will do, Im liking the ability to zone off everything, individual rads and even the manifold as an entity, I’ll make sure it fits first though, 28mm sounds right doesn’t it? That was what I bought, only size they had after 22mm and it sounded reasonable. yeah need to take some up to date photos, will try and get some, just absolutely flat out with trying to get stuff done, amazing how much time it takes to decorate properly. Plastering went well well for a first time, yeah it’s not perfect, but even for me a perfectionist I’m really pleased with it and all for £25 and a good amount of effort! Needed the exercise anyway lol

Yeah i've bought some caps for the end if it becomes an issue, i had thought that myself, but it seems fine at present, it is angled upwards, so isn't totally flat. Cheers for the heads up. Will get some more photos of progress up soon, taken delivery of our engineered wood flooring today, hoping to start laying that this weekend ? Oh and we've had building control sign off too which is always nice.

Exactly so, yes I used MLCP 16mm pipe, and it worked brilliantly. So the only joints in the system are the manifold, the radiator valves, and the 22mm copper to plastic connection to adhere to the boiler guidelines of using plastic pipe (first bit has to be copper). Really impressed with the 16mm pipe, would definitely use it again, as you say its so easy to shape, and with a pipe bending spring, you can get almost any angle you want, and it stays put. Funnily enough the few odd leaks I had were on the traditional 15mm connections, all of the 16mm eurocone connections were spot on.