Roger440

Correct. Just money "for chums".

Wood fibre lime plaster straight onto the brickwork Though i will caveat that by saying, the decision was ultimately driven by the fact that flooding is a risk. So things like woodfibre boards had to be ruled out as "if" it were to get wet, there might be a need for remedial works. Part of my self imposed remit was "operatin 4". Ie, withing 4 hours of the last drop of water going out the door, id be on the sofa with a cup of tea! That requires an arrangement that will be unaffected by a couple of hours of water at a depth of no more than 1 inch. It does, however, mean that heat loss through the exposed wall will always be significant. Without factoring in flooding, i would have probably use one of the direct onto the wall solutions based on my research. The challenge with all of this, is there are so many variables, and you probably wont know if you chose the wrong route until a few years later. But as mentioned earlier, i nearly bought a barn conversion that had been done with a cavity which wasnt without its problems. Though i will never know how bad they were. But it made me wary.

Agreed. This forum is excellent. A lot of very knowledgeable people. Unlike myself. Your comments about moisture transmission make sense. If you were attaching it to the walls. But you are not doing that. Surely, what you are now doing, is to all intents, no different to traditional cavity construction. Where the inner leaf is usually brick or block. And on newer construction, with celotax nailed to the inner leaf. So no meaningful moisture transmission possible. Im not convinced you are gaining much with woodfibre other than extra cost? Mind you, ive not really looked at from that angle as its not a route i went down. Hopefully someone will come along and point out why im wrong?

Whats the theory behind woodfibre rather than celotex etc, given that its isolated from the main building? Surely thats just more expensive? What constitutes "extreme" regarding the weather? Rain?

I quite like the look of it as it is. Pointing in lime i presume? One of things for me with a cavity is that its is, as you say, just a rainscreen. That does mean, however, the wall is detached from the house and it will always be a cold wall, so will encourage damp and moss growth etc. Though i cant say i had any practocal experience of that. I did look at a converted barn a decade or so ago. That had been done with a cavity. There were obvious signes of damp near most of the windows, i guess because at the point the cavity is bridged at this point? Didnt buy it so never found out. I spent hours reading, then used some common sense. If i was doing it again, id do exactly what ive done, so no mistakes to share. Which im pleased about.

Saveasteading is right, there has been lots of debate on this. He even seems to be coming round! Have a read of the 2 recent threads. Im firmly in "no cavity camp", assuming of course that wind driven rain isnt an issue. Which i guess its not, especially as, i assume you are putting the render back on the outside? Following the renovations on my house, the views of what one might call hardcore lime purists, so no modern materials that restrict moisture movement, do appear, im my case to have worked 100%. How damp is it? Im not sure id have layed concrete. Thats likely to drive the damp to the walls. Depending on how much there is? Have you looked here at their internal wall systems. https://www.lime.org.uk/ I found there periodpropert forum very useful specifically for "old stuff".

Thanks. Interesting setup. Ref the interest, doesnt really apply, as if i didnt spend that money, it would only be because im not buying that particular property. Buying an equivalent property with a connection, would, inevitably, cost more.

I know it doesnt include the capital cost. Rather depends on over what period you want to amortise them too. For someone like scottishjohn where the DNO want £20k to connect anyway, then its starts to look more sensible. I cant imagine it would ever make sense if you actually have a grid connection. I looked at it as i was looking at a property with no connection and no realistic praability of one. Certainly not for £20k! I assume you set up feeds into the grid too? How long do you anticipate your batteries lasting?

This is why i bought a diesel genset.

I strongly suggest reviewing the stormdry for its ability to allow water to pass OUT of the wall. The test results show a decent reduction in ability compared to untreated. There are better products on the market for a breathability perspective. Whatever you use, it IS a permaent solution. Its not like you can remove it afterwards! Dont forget, if you add any one layer of something non permeable, then doing any others is waste of time. Whatever buildup you install either in or outside, will only perform to layer with the least ability to breathe. That includes your pointing.

Yes, all of that. Update. Array was 6.8Kw. But you can have a bigger one if you want Lithium batteries. 30kwh Decent perkins genset too ui f i remember correctly?. He quoted the 15000i on this page but with a 6.8kw array. Mainly as i would have a releatively power hungry workshop. For a big house the 10000i is normally enough. https://www.energy-solutions.co.uk/products/easygrid Just need to add waste heat recovery from genset exhaust for the best possible result. The guy was really helpful. As he said, its like being connected to the grid from an end user perspective.

Just today i got a ball park cost for a turn key off grid system. Enough for a house and a workshop. £40K + VAT. That included everything required except installation. No user input apart from keeping fuel in the tank. What i found interesting was although a significant capital cost, was that that the cost per KWH was very low. In their best example, 9p per kwh. Ok, its PR and best case, but given current prices, and the near certainty they can only go one way, in your position may be worthy of consideration. Especially if its going to cost £15-20k for a grid connection. Who will then charge you 30p per Kwh for ever + price increases.. They quoted me the 15000 version, which is overkill for a house, so would expect a slightly lower cost. https://www.energy-solutions.co.uk/guides/off-grid-guide.pdf You just have to get past a diesel genset being part of the solution......................

No, no no! As per Simons post you are decoupling the wall from the "house" with all the issues that "might" bring.

I didnt quite want to put it like that, but pretty much, yes. Niether architects no building inspectors have to live with the consequences and subsequent costs. You do. Assuming you stay there long enough. Go and have a look at a few older ones that have been converted. I did. I wont buy one. Essentially having to undo work done to do again and pay the premium for a "done" conversion. People have been buggering up old houses with cement and gypsum for decades. Thats not debateable, its fact. Mostly builders, building inspectors and a bit of architect help too. The industry is rife with people with no understanding of moisture. Do a search on some of Jeremys post on condensation issues with SIPS for example. Im not expert, just an enthusiastic ametuer. But i know what i see. I also try to use logic. That helps too.

Blimey, is this still going on? Ive said what needed saying. Simon has more patience than i and posted again above. With the answers. However, you still want to do something different. Im at a loss why?

DIY, block paving everytime. Cheap, simple to lay, and in the event it does move (because you didnt do it right) lift up a local patch, add sand and smash it back down.

Pretty much sums up what will happen. Or rather is happening. 5 years from now, lots of hand wringing, statements about lessons being learnt, lots of companies having "disappeared" as fast as they came, clutching vast sums of taxpayer cash. And lots of people with ineffectual heating systems. As inevitable as night follows day.........................................

I was thinking water based solar to heat water, both DHW and heating circuit. No grid connection required. Just a very big tank. Supplemented by boiler, GSHP, ASHP. Maybe some electrical as per Prodave. Granted, not going to be easy on a small site, but with a bit of space, might work?

Given that electric, gas, and oil prices are all only going one way, both through demand and government market distoring measures, surely as part of any installation you should be considering solar, thus reducing reliance on whatever energy source you choose. Whilst the hardware may cost, its a much more certain running and payback cost. I think even this government would find it hard to tax sunsine!!

The evidence on the ground says plaster doesnt breathe. Do you have a link tosomething that says it does? Though im inclined to believe the evidence of my own eys.

Im not bright enough to do multiquote, so take these in order 1. I agree. Ludicrous idea. 2. You dont need an inner wall if its not damp. We are going round in circles here. The insulation i discussed in my previous post. What do you mean the existing wall will "not be available".? 3. In which case, the various solutions available would seem to make more sense, and applied to a dry wall. 4. Who cares? It is what it is. Its 2 walls only at ground floor level only. There is nothing i can do about it, especially in light of the flood risk. Any solutions that will survive flood, beyong straight lime plaster, are not compatible with keeping the wall dry long term. 5. Dont tell them? Lie? Thats what i did. BCO adds nothing to the process other than likely trying to impose inappropiate solutions. Which will potentially cost YOU money when they dont work. Frankly i have NO time for the process. I have a suite of certificates for bits of the house generally. NONE of the jobs comply with the regs. All signed off though. Totally and utterly pointless system. Architects? Mostly i suspect, dont really understand. For every 50 jobs, they probably get one where its an issue. Its not a surprise unless you find a specialist one. You would take a transit to a VW specialirt to get it fixed would you? 6, Ive said all there is to say.

Im unclear why you need any holes? Once the building is complete, and you have stopped the source of water ingress, why do you need to do anything else. Im at a loss as to why you need "holes". As i explained in my earlier post, i too had wet walls. I dont now. There are no holes. Still dont understand. And what is it you have "one chance of doing"? With my solution you will add NO thickess to the wall. Do nothing, apart from reistate a roof etc and let it dry out. IF you want insulation, and ask yourself if you really do in this instance, then the usual lime product supliers all offer IWI systems that DONT leave an air gap. Why are you simply not using one of these? Some are LABC approved. No air gap, less added thickness. Completely breathable. Problem fixed. Ive chosen NOT to insulate, just lime plaster internally. That decision however is primarily driven by the fact that i am flood prone, and all of the options use various natural materials such as woold, woodfibre, cork etc. These are unlikely to cope well with flood conditions. Lime plaster will likely be fine given such flood events are very short duration. Were i not in this position id be investgating the various IWI optins and selecting accordingly. As Simon said, adding bitumen, realistically, is only likey to add problems. Its the go to solution by builders who are ignorant of how to deal with older buildings. Its plenty common enough. My neighbours did it.

Surely its capped with a vent? Rather than open to the elements? If its still open, cap it with a vent. Then buy one off these: https://www.chimneysheep.co.uk/ In the summer if you fancy a bit of cooling, pull it out.

The bit about no roof was a key detail i think you left out! But, never mind. If you say it will be dry, why do you want to line it? I dont understand this. You also, correctrly, mention losing the thermal benefit of the masonary. Your proposed scheme does exactly doesnt it? So you will surely need more insulation thickness that you could otherwise reduce. Once the wall is dry and repointed propely, driving rain isnt likely to penetrate 600m. If conditions are that bad, render it. I dont follow your thought process here.

I missed this post. My answer is, your wall is wet. It shouldnt be. So fixing the wet issue is fixing the problem rather than applying a cover up. Will that be easy? Possibly not. Im not sure what i did was easy, but it was logical and highly effective. I certainly woudnt run a liner up the wall. Sure, if its a quick job to tart it up and scarper. But long term, you will make the problem worse as you have removed an evaporation path. Assuming its lime mortar, it will decay and break down. How quickly? who knows. I know im an outlier compared to most of the building trade, but im firmly in the fix it once, fix it right camp. The answer to your opening line is number 3.