DIY Disaster Averted: My External Wall Insulation Saga

With my DNO coming to move my electricity cut-out I needed to get some external wall insulation up on the wall where the new electricity box would be. I ordered everything I needed from EWI Store and as a complete beginner attempt to install the insulation and render the wall before the deadline.

[@pablotrobo]

I'm about to start the process in my house and this comes very handy. I have no experience in construction but love the challenge. This video gives me some parameters to use andadapt to my project. Thanks for sharing this info and for the straight forward approach

[@RodMcBain]

Thanks for watching and commenting, hope your project goes well!

[@SVThailand]

I think one of the reasons you got such a flat finish was you used a light at night which is the most revealing. That's how I check drywall when I do walkthroughs on homes is I'll turn the lights off in the room and use either a flashlight or a bright work. Light shine along the wall and it'll show me any imperfections or waviness

[@RodMcBain]

That probably did accidentally help!

[@multirole240]

Very interesting video.Thanks for giving an insight in to the process and material employed, and most useful the things that can go wrong (as with any job). Well done.

[@RodMcBain]

Glad it was helpful!

[@pitbladdoassociatesltd]

Not a fan of the External Insulation, but well done. Just be carefull with the cill. With the warm of the summer sun the various materials will expand and contract at various degrees and relying on products like silicone can cause hidden problems. The cill could be a location where water sits under, getting behind the render or the insulation and soaking in water. The age of the property I'd say it didn't have a cavity brick wall so be careful of damp issues in the coming years. If not having a cill extension, a chamfer along the top edge of your render under the cill would be beneficial. Nice looking job though.

[@RodMcBain]

Thanks for the comment, useful tips in there. I did briefly think about adding a chamfer to the insulation under the cill, fortunately it's in a very sheltered area and doesn't get much sun or rain, I'll keep an eye on it and go back and add a chamfer if needed. I think in future I'll just go for the thicker cheaper EPS boards and add a cill extension. It is a solid 9" brick wall, In an effort to keep the video short I didn't show this, but I did add a row of dryrods as a precaution against rising damp, the the existing slate DPC looked sound so probably not required. Over the next year I'm planning to wrap much of the existing building with a modern extension and add a MVHR unit to control indoor humidity. I guess going for EPS in future would also help, they appear to be more vapour permeable.

[@firsteerr]

many people nix external insulation and its down to the ever old story of incorrect installation as long as all the steps are followed correctly and the right and recommended material's used its a great way of insulating your home to a high level with relatively minor works on down pipes etc.

[@RodMcBain]

Time will tell if I did this properly 😀 Seems like a no brainer to me, less mess than internal insulation, you don't loose any space and you end up using the brick structure as a thermal mass, thanks for watching.

[@supetrkov8198]

It's very nice to watch this wonderful boy work!!! Happy New Year!!!

[@RodMcBain]

Thanks!

[@pumpkinhead456]

Great stuff, good job Rob!

[@RodMcBain]

Thanks, glad you enjoyed it!

[@tomashubelbauer]

This channel is a hidden gem!

[@RodMcBain]

Thank you, hopefully with time it will be less hidden 😀

[@GreenTorque]

Great job, one slight mistake though. You didn't wrap around the starter track around the corners. This should have been done by cutting 45 degree angles at the end of your cut to match the next piece. Rodents can burrow up into the EWI where there's no track

[@RodMcBain]

Thanks, those corners were seriously lazy, I was aware I should cut at 45, but figured it would make little difference to supporting the EWI, I didn't consider the mice 🤦‍♂️ I'll stick some steel mesh under there to keep them out.

[@GreenTorque]

@@RodMcBain would you also consider insulating to ground level? Thermal modeling and thermal cameras show that it makes a significant difference and reduces thermal bridging. You can useexpanding foam to seal between the plynth and EWI you’ve already installed. Fair play, you did a great job overall, It's not an easy system to DIY because there's a lot of details that can be overlooked. There are other details you could have done to improve the installation but that's gold standard level and takes more time

[@craigchamberlain]

Hey Rod, very interesting video as always so thanks for sharing. We live in a cottage in the countryside of North Ayrshire and although I"m very much in favour of saving energy, I'm not a great fan of EWI as a means to that end. That said, your video does make it seem much more attractive than I expected. Our cottage is partly a very old (> 150 years) building with 450-600mm thick stone walls coupled to a 2008 era extension. We recently had it painted at a cost of £4650 so are not in a hurry to hide that painted render behind insulated panels. Our energy efficiency is not as high as I would like it to be, but I'm hoping we can achieve the level we want by reducing draughts under skirting boards using memory foam tape and improving insulation in the loft space and walls as we refurbish each room. Did you get a thermal imaging camera to evaluate you property before you started work? I'm very tempted to do that before I start.

[@RodMcBain]

Thanks. It's understandable having spent all that money on painting that you don't want to hide it away. I bought myself a Topdon tc001 thermal imaging camera for my phone last year, it showed the walls were the coldest spot in the room. It also showed I need to do the roof insulation but being a bay window it means taking the tiles off to get insulation up there, probably a summer job.

[@jeffpowell1616]

What’s the payback 😅?! I recently had a new EPC. One of the recommendations underfloor insulation @£6k fitting estimate for £250 per year saving…

[@RodMcBain]

It's not really feasible to work out the payback for this small 10m2 section of wall, but in old buildings like this with solid brick walls around 1/2 the heat you put in makes it's way back out through the walls. It's also important to consider that the payback is not always financial, many of the the changes that make your home more efficient also make it a more pleasant place to live, hard to put a value on that.

[@kevinhartle4494]

@@RodMcBain good answer. I think it's as much about making your house comfortable, as achieving a payback. Nobody asks about the payback when you fit a new kitchen! If you are considering payback you need to include the fact that if you can improve the EPC band, say from D to C, then the value of your property increases. There are sites online that will give you an idea as to how much this may be worth.

[@aurick861]

wouldn't it have been easier to just get new sills? Removing all that render seems like a lot of work. Cheers!

[@RodMcBain]

It was a lot of work and if it was just for the extra depth I might not have done it but the old render was blown and cracked in many places so would have needed repairing first. I think the normal solution to this is to use over sills to extend the existing sill.

[@Joe-s2y4m]

Just so you know only ESP insulation should have the holes cut and plugged. It not done for Kingspan K5 because of its properties and also will destroy a ESP hole cutter. Nice work though

[@RodMcBain]

I read your comment and thought no, the instructions for the k5 defiantly had fixings in pre cut holes. But looking again you are 100% correct, I must have just maid an assumption, thanks for pointing that out, will make it easier if I need to do it again and explains why I destroyed the hole cutter.

[@kevinhartle4494]

@@RodMcBain You're not on your own. I've installed a mix of EPS and K5. I installed the EPS first then broke the hole cutter installing the K5. I contacted the EWI Store who told me it's not necessary to sink the mechanical fixings into the K5. Well done for taking on the job yourself. I hope it's made a good difference to your heat loss.

[@johnohalloran915]

Have you found the external insulation made a difference???

[@RodMcBain]

Yes it's made a big difference, it's hard to quantify but before the insulation we had constant condensation on the wall every morning, that problem has completely gone.

[@johnohalloran915]

I live in a timber frame home..upstairs always warm..but downstairs ud know when the heat goes off...