Redbeard

I think lots of BCOs are requiring 'dry' and mechanically-fixed ridge tiles now. You may have to live with the colour, but I am a believer in straight lines... Do you know the make? If so send pics to the manufacturer and ask if that complies with their expectations. Then invite the contractor back to tell you to your face that that is a good job.

I'll get me coat...

😂 No...it sounded vaguely funnily like Dee Dee Ramone but with a little DIY moan mixed in. I must be being a bit dim also because I'm not sure what you're referencing? I'm aware of MZ bikes and the former East Germany but it's like one of those questions on the 1% Club where your brain just won't make the connection! 😂 Sorry, a bit tortuous, but the former East Germany was the 'DDR' (Deutsche Demokratische Republik), so a 'DDR moan' might be a grouse about that former country. I obviously lived too long with MZs (11 of them IIRC!)

4 hours ago, saveasteading said: I didn't know this. Can you explain why the toothing helps get it flat? As a poor plasterer, I like the products with a high latex content. It is stickier to the wall, less effort to float and takes a while to go off (for second chances) Nod said: It doesn’t base coat needs to be flat and lightly scratched Think he’s getting mixed up with top coat A toothed feather edge is used to get the air out Then flattened back down Sorry, I was not assuming much 'out-ness' on the substrate. The toothed trowel approach (which I always used for plastering and rendering on wood-fibre) does not get it flat - simply helps you keep even as each subsequent coat goes on, so yes, you do need to get the first coat fairly right. Bear in mind I am talking about renders and plasters designed for thin-coat application, not at more 'traditional' thicknesses.

@nod is right, but if you are really wanting to do it yourself the 'toothed trowel-depth-guide' method works. I think perhaps my description is more complicated than the doing. Just a bit of practice so as not to try to 'go over' when the coat below is too wet.

I think I would be tempted to buy some base-coat EWI-type render. If you have never done any before I would suggest use a 10mm toothed trowel, then let that coat stiffen up a little before doing a second coat with an ordinary trowel. The 1st coat will act as a guide for the 2nd. You may not need mesh but I think I would use it. Lightly 'float' the glass-fibre mesh over the 'peaks' of the toothed coat , the=n trowel on render till the mesh is no longer 'ghosting through', or as close as you can get. You may need to do a final base coat to lose all the 'ghosting'. Final final coat (after 4 days, IIRC) is self-coloured top-coat 'gritty' render. Lots of people sell this stuff - sometimes local merchants, but I have used EWIStore a lot.

You didn't ever have an MZ motorcycle that you were dissatisfied with, or a grouse with the former East Germany, did you? Your user name might suggest it!

Welcome. 25mm of (breathable) wood-fibre could give you a U value (heat lost in Watts per sq m of building fabric per degree C.) of around 0.85W/m2K - around half of the heat loss (1.7W/m2K) for the uninsulated wall. Better than a poke in the eye with a sharp stick but the Bldg Regs target of 0.3(or as close as you can get without seriously risking interstitial condensation (condensation within the slices of the insulated 'sandwich') ) is a lot better. 100mm would give you about 0.35.

I had not noticed the ref to opposite directions - in fact I still cannot find it. Sorry if I missed one. All I saw was this: ...so in my mind there was as much a chance of 'hills' and 'valleys' lining up (leading to effectively no increase in depth) as there was of 'hills' and 'hills' coinciding (10mm either way and you get a different result). If you do it each at 90 degrees then maybe you could let one coat stiffen up a bit first? (Still not certain what depth you'll end up at when it 'sits down')

I use a 10mm notched trowel when I want a 6mm-ish bed, as the angle of the trowel 'closes it down'. A 6mm trowel 'closes down' to about 3mm depending on the angle.

Would the planners be interested? Surely this is a Building Control and Compliance thing?

From bitter experience... if you use a hot air gun (on low!) wear gloves. If you get it too hot your fingers will break through the oter layer into the molten hot butyl. It sticks and it burns. Can't tell you how I know.

dpc? I guess...

I could be wrong but I believe that a lot of cavity wall insulation companies are members of a self-certification body, so they can sign off against Bldg Regs. However I feel pretty jolly certain that they could not sign off a job which was not a cavity wall.

Yes, I think you need BC. You already have the calcs so do a Building Notice, which is just a pro forma telling them briefly what the works are and when you will start (no less than 2 days from the date of the notice) ... and a fee. I have not read all the thread but it is structural work. Any that I have ever done has needed BC approval.

Hi, when you say that do you mean you feel you have no recourse to the builder? Or does 'we...' include the builder re-doing the work? It is not ideal but while you would almost certainly not get a satisfactory result by patching you may be able to re-coat entirely. Not that I am recommending this at all, but 16 years ago an apparently well-thought-of insulation company managed to quote for 50mm phenolic EWI (which would then allegedly have given a U value of 0.35W/m2K). They then had their sub-contractor (part of a nationally-known company which subsequently dissolved) do the installation. The sub-contractor used 40mm board. When questioned I was told 'we always use 40mm board...! What they should have done then is taken it all off and done it with 50mm. What they actually did was to adhere 20mm phenolic on top of the top-coat and re-render. While I cannot commend this slap-dash approach what it does prove is that base-coat render has a good hold on underlying top-coat render after 16 years. So if you hold any money owing to the builder you could, after consultation with the System Provider, consider asking the builder to have a trusted renderer do it again (base-coat and top coat) over the existing... (Or tell them to hack the lot off and do it right. Is it on EWI or block?)

Yes, but cob has worked for hundreds of years in the UK. It has also failed spectacularly where modern materials (sand/cement renders) have been used to repair it. Yes, it is 'newer', but there is at least one straw house in USA over 100 years old and many an awful lot older than 20 years. Straw bale in the UK is pretty young, so yes, 20 years may be 'the norm' in UK, but arguably (and I haven't checked the true figures) because the 'start' was only 20 years ago. It doesn't mean they won't last another xxx years+. You are right that lime and a big roof oversail will help a lot.

First hit on 'Neighbour consultation permitted development' gave me: https://designfor-me.com/project-types/extensions/what-is-the-neighbour-consultation-scheme/ So a 3m extension will not be consulted upon with your neighbours, and a 6m one will, AFAICS. I do not know any more about the specifics of the consultation procedure - can a neighbour somehow block a development, for example - but there is an appeals process, it appears, so I am guessing that a 6m ext'n is not a 'done deal' till it's 'done'.

Very well done! I'll stand down my tape then!!

Is Ubakus German, or did I make that up?! If it is, I wonder if they do not use the IP/90-type Perimeter/Area convention, which gives a lower 'base case' U value than the old 'Uninsulated floors are 2' - IIRC then you'd expect a higher U value. But then I may be talking rubbish since, even if it's German, this appears to be the English version, so maybe it does use IP/90

(Sent PMs)

Packers for slightly-out-of-line studwork, I had assumed.

Bu**er! That was my favourite! Hope you find it.

This?

I think last time I did a B. Regs app with more than one element the cheapest one was halved in price, so in your case it could be £809 + £275.50. I think I would be tempted to do it on a Building Notice (Simple Bldg Regs app with a brief descr of works and no other detail) rather than Full Plans, but then I'd be building it myself. Depends on the degree of complexity and how much you trust your builder. Planning looks like it ought to be really simple, I *think*. You could draw that, and thus do the Plg app, yourself, perhaps. Re struct eng'r I suppose you'll at least be changing lintels, if not roof timbers, so yes, you need them, I think.