SimonD

I've certainly seen a lot of examples, including here on BH, where the professional input is undervalued and people try skimp on it. I'd agree this is counterproductive and often has a detrimental effect on the project as a whole, especially when you aren't experienced in house construction. However, there are some of us that are aware of the benefits of this upfront investment and are willing to pay for it. One thing I did before even getting any architect involved was to pay for a topographical survey so it was already on hand when looking for an architect. Something I used to great effect in understanding costs associated with some designs as I was able to get quotes from groundworks companies based on the survey (we're on a significantly sloped site). The problem as I see it is that despite having the will to pay for these services and put the time into the design decisions, there remains what I see as a gap in the satisfactory provision of those services in construction. For example, we tendered and met with about half a dozen architects, all of whom visited our site. I paid some of them a fee to make the initial visit to talk about our plans. When receiving their proposals, not a single one of them met our brief. Both my wife and I wondered whether we had dreamed up the meetings we'd had because they were so far off. In desparation we then engaged the services of an architectural technologist based on a recommendation, but even then the design proposals that came back were underwhelming at best, totally impractical at worst, so we paid him for his time and went in search for someone else. I won't even begin to describe the atrocious service we received from the first structural engineer we appointed (introduced by the architect). He even had the gall to bill us for an incomplete scheme and when I went back with a list of what was missing, he still didn't respond and his company chased the invoice. Needless to say, I got rid of him and eventually found someone else, who did turn out to be good. I disagree with this. If you're a professional dealing with a layperson as a client, it is up to you to ask the questions to elicit and grasp the requirements from the client. It is not for you to expect the client deliver those requirement as the client cannot be expected to know how to articulate them adequately or know the extent required (or even the potential ramifications). If an architect, for example, after 7 years of training is still unable to do this, then I'd have to wonder what is missing from their education as it is clearly essential to a good design process. It is also up to those professionals involved to manage effective communication, with their client, and also everyone else involved in the project so that the necessary questions are resolved and accounted for ahead of time. The architect we chose in the end was excellent at eliciting our design requirements and at the same time was able to enhance those with his experience. It took me a while to appreciate this side of his service. However, his biggest and most unacceptable failing was that he wasn't honest about where his technical limitations lay and instead proceeded to advise us incorrectly in this regard. However, there were several other aligned professionals who also provided poor technical advice. It's this incorrect advice that has cost us significant money, not changing our minds about sockets, or other such design elements. My own experience could simply be dismissed as poor decision making or bad luck on my part but there are enough stories on here and from people I've met to suggest I'm not such an anomoly.

I'd agree with that approach and followed it. We had full budget plus a little over 20% contingency. What we didn't know beforehand was how badly advised we'd been by the professionals we'd engaged to help with the project. As a consequence our project ended up almost double in size. Then we were hit by various global crises that saw our budget shrink even more and so everything was far more expensive than originally priced. And believe me, I'd nailed down the prices before even commencing with the work. This is what has led me to believe that you have to beware professionals in the construction industry, as I've generally found the service we've had to be particularly below par. I don't seem to be the only one that's had this problem either.

It's a known predicament of human nature sadly. Lao Tzu said over 2000 years ago that you should always prepare for a journey to be much harder than you imagine. I wonder if he'd built his own house. Isn't that just the case. You get to the point where you just have to carry on. However, on the bright side, it is a major achievement to build your own home, just like it's a major achievement to start a successful business, be a successful athlete, or achieve anything of note really. All of those things take their toll and demand some hardship, it's just the flavour of the hardship. I myself am far less stressed about the building game and running out of money, being delayed and seeing my boys growing up in a caravan than I used to be when working at a senior level in a large company, having to deal with all the associated BS and living subject to the whims of the firm, so to speak. Definitely no regrets here for me.

+ 1 Yes, the brace is diagonal. The dropping depends on how well the ledges have been fitted together with the quality of the wood as the door structure puts a shear load on the nails/screws, but there is also some friction between the ledge and planks, but not very much. Ideally you want the hinges fitted on the ledge too. Overall, I don't think it's a particularly complicated job to cut a rectangle, insert a frame, insert a pane of glass and bead on both sides, plus fit the lower brace.

Looks like a ledge & plank/ledge & braced door which means this would have to be reconfigure to retain the structural intengrity of the door, but definitely doable. Here's one example: https://authentic-reclamation.co.uk/stock-item/ledge-braced-door-with-glass-panels/

It's a tough ask. But I reckon there are a couple of strategies you can use. You can get a 50mm stud wall built up for about 54db reduction using a type of sound board resulting in a total wall thickness of about 95-100mm. Buildup is sound plasterboard/50mm stud with either air or mineral wall insulation/acoustic board (30mm), then you've got either a plaster skim/tape & joint over those. One of the problems is your studs which should ideally be staggered to reduce sound transfer. If you left your wall at 140 and used stagger 38 x 89 studs with zigzag acoustic insulation you'd probalby be fine. Another strategy is slightly more complex, which would be to build your stud wall with sound plasterboard and some acoustic mineral wall insulation and then measure your sound spectrum with the washing machine and other appliance within the new space. Based on your results, put in some measures to attenuate the troublesome frequencies, in particular the fundamental frequency. You can use soft furnishings, cork wall boards and other sound deadening materials for this, even a simple helmholtz resonator in the corner of the room can work very well. Doing this would mean that the spl affecting the walls would be significantly reduced and therefore less problematic. With this approach you can also reduce the sound coming through the doors too. Part of the problem as I see it with acoustic wall design is that in the designs, the acoustic properties of the adjoining rooms is never considered, which is a bit of an oversight if you ask me.

Brilliant. I'm always amazed when I see stuff like this and have to ask, who on earth found this out and how? ?

So many of us on here go through this, it seems to be a right of passage for a proper self-builder. In case it's any consolation at all, I'm also probably a year behind, I gave up one of my businesses to do the build myself and last week after paying my latest credit card bill realised we have about £300 left of our total budget (and yes, that's the correct number of zeros). Knew it was tight when we started and I'd hoped to at least get the heating system and temporary electrics moved to permanent and sorted before running out of money, but will now have to save for those. I can't start up the business again as it would take at least 18 months to see any real income. My builder is rubbish too as he's sat drinking tea, writing rubbish on here right now when he should be doing something useful in solitude on the site - yes, everything moves slowly here ? Sanity and health must prevail, so really do try to relax into the process, have a drink and know it'll all seem worth it when it's done! ?

Have you considered cork floor underlay? This is available in mm steps from 2 - 10mm in rolls. You can see these at spduk.co.uk. I recently bought 100m2 of the stuff from corkfloor.co.uk at a great price but you'd need to speak to them on the phone for thicker than 2mm rolls.

I spoke to a local surveyor and asked him to look at the property and review the insurer's report. He came back to me with a view regarding required remedial work plus a ballpark figure - it was complex due to banking on the side where there was subsidence meaning deep piles. I then assessed the rest of the site, for example poor access and neighbour close by whose garden we'd have to use for some of the work. Added my contingency and offered 200k below asking price. It's definitely worth getting it looked at by someone with relevant knowledge and experience.

As @nod suggests, I'd wait for the Structural Design first because you'll need to know if this requires any design revisions. I found it's also important in that it helps to hang the build together so you know more about how it's going to be built. I know there have been plenty of times I've felt overwhelmed with the number of things I've got to detail, make decisions on and finalise, but often it can be helpful to try and break things down a bit and then deal with one thing at a time only. Are you able to put together a list of what you need to do and by when for the full technical drawings and which decisions are actually down to you and not the architect, SE etc?

Honestly, if there are signs of subsidence then you're potentially walking into a money pit. When I was looking, I found the most amazing property with just stunning views. The only problem was that it was being sold following an insurance assessment re subsidence. The so called engineers report from the insurance stated it was settlement, but our surveyor said the report was useless. The risk was too great that we would sink so much money into the ground without anyone seeing it that I took that risk off my offer. The seller didn't accept so we walked. Sometimes it's just better to walk away from something despite the emotional investment. If you're feeling like this now, just wait until you're committed with your money and a problematic development and then the stress will really hit you.

Sounds like you're making progress. How come?

Studies in Sweden back in the mid 2000s found that new build airtightness reduced in the first year simply due to settlement of the building and materials. It was proposed that airtightnes tests should be carried out something lie 12 months after construction as this would be more accurate. And this is from a country that has far higher building standards than your UK developer. I think this thread is giving the green plastic a bad rap because that's where the moisture is being found. Simply removing this yet using an impervious insulation material behind the plaster isn't going to fix that at all so I'm not sure why it's even being suggested as a better way to build to avoid this. I agree. The problems as I see them are to do how we build wall systems with impervious materials and fail to ventilate properly - a recent government study found that the majority of new builds did not even meet building regs for ventilation requirements. I'm also still surprised the option of moisture open wall systems almost never enters into discussion.

Clay ground and 400mm to 1m existing foundations does not necessarily preclude second floor extention, but does require the right designer and structural engineer. Solutions can include making the 2nd floor loads less than existing, especially if existing has concrete roof tiles, pad foundations to support point loads, ring beam around existing ground floor walls. I know this because my project uses all of these things and we've got 300mm foundations in places, and that's 300mm below dpc which is 150mm above ground level. How many trial pits/trenches have been dug to obtain information? In ours too few so poor assumptions were made until I insisted on digging and investigating more. When was the original house built?

How heavy are the windows and the bifolds? This will dictate what kind of suction lifters to buy and then don't buy cheapo ones, buy ones that are clearly specified for a particular weight. If you're lifting expensive and heavy windows it's also a really good idea to have a suction guage and certificated lifter so you know it's on properly. I've had a non-gauge one let go while moving a window around and thankfully it was still suspended on a proper gauged one at the time so the window just swung around a bit. In terms of specific products, I've got a couple of Faithfull triple pad lifters, Faithful 2 pad lifters and a Grabo. I've used the Grabo a lot as it works on everything from windows to paving slabs and more.

I've had some cheap Chinese hardwood ply that was full of voids. Possibly okay for basic sheathing purposes, but not nice to work with. I was also at a merchants recently to buy a particular grade of ply. When I checked, the product they wanted to sell me only had 6 plys and obvious voids whereas the product I was asking for had 7 plys and much less visible voids. They even had another pallet of the 7 ply stuff but refused to open it for me and refused to accept it was a different product. So off I went and spent my money elsewhere...

Looking at your drawings, they correctly specify the use of WBP Plywood as the substrate for the standing seam roof. If you do decide to go ahead, make sure your tf builder complies with this specification and doesn't use osb. The spec on the drawings is correct for the standing seam with a ventilated cold roof. As it's a change of material, you may be correct in that it might require an amendment to the planning approval - are there any conditions? You will notice the difference between standing seam and whatever the lookalike version is called, especially if you're looking down on it from a window above. Best thing as always is to see if you can look at some local installations to make a comparison and therefore more informed personal decision. Yeah, a big difference there! ?

+ 1 to airtightness tape or similar. For masonry to other materials I've recently become a fan of the Soudatight LQ liquid membrane that also uses a goetextile tape to seal larger gaps.

Compared to Greencoat PLX, a single ply standing seam effect roof will look cheap and fake. I also suspect it won't come with a 50 year functional guarantee that you get from Greencoat, with a much longer potential life span if it's then maintained. I suspect your builder is just reflecting a lack of experience with standing seam and going with something that seems easier - easier for him - rather than for the overall benefit of your house. With a 13 degree pitch, there is no problem at all with penetrations within the standing seam. Yes, they take a bit of time, but nothing to phase an experience standing seam installer. Before making a decision, go and have a look a the fake standing seam solution and then go and have a look at some proper real installatios and then make up your mind. Hold up a little bit here. While osb is okay, the preference for a metal standing seam roof is 1 sarking, 2 plywood. Sarking provides better ventilation to the back of the steel roof, plywood for convenience and good nail pull out resistance for the fixings. OSB does not have great pull out resistance for the nails used by your traditional metal roofing contractor, and screws are much preferred. This adds to time and cost. At the moment, you can get plywood for pretty much the same price as the osb. Talk to you roofing contractor before the tf supplier completes this part of the build. Also double check the roof buildup. Is it a cold roof with ventilation between insulation and final osb or is it a warm roof? Again, if it's warm, make sure you get your roofing contractor in asap to ensure it's all detailed correctly. I don't think either of these statements are true re traditional standing seam roof. A recent discussion here on BH re rooflights installed in a non standing seam metal roof attests to this. Also, a traditional standing seam roof installed well will outlast most if not all the non-standing seam roofs on the market and with completely hidden fixings you're never going to have a weakness of deteriorating screw fixings, which is pretty much guaranteed and well known. Oil canning effect can be due to several issues, but you can reduce this risk by using narrower seam and other methods, but on most installs by a good contractor, this isn't a problem.

First thing I would question is the lack of ventilation in the cavity between existing wall and new timber frame. Who has designed this and what is their justification for this? You're going to have to be very careful about detailing the inner wall and any floor/wall/ceiling junctions correctly for airtightness/vapour control. If the cavity has no ventilation there is risk that moisture levels reach undesirable levels, which could result in mould growth. Ventilation is your friend here. I don't think it matters whether you use osb or ply. It can be easy to assume from this thread that all ply is the same. It isn't. A decent quality sheathing plywood will be fine for the life of the building. The problem is that there is some real rubbish out there supplied from builders merchants that don't have a clue about the timber they're selling and people want cheap, cheap, cheap. Any timber product, including osb will deteriorated if moisture levels are too high. My suspicion re the mould in the OP is that there has been condensation on the plywood due to natural humidity fluctuations and this has fed natural sugars in the timber, plus there have been some spores from old furniture that have added to the problem. Once the moisture levels in the building settle down and the sugars in the wood have been consumed there will be no more growth. If your SE has designed the TF with sheathing, then yes. But basically all timber frames need some form of racking resistance. This is supplied using either diagonal studs at required intervals within the frame, or you use plywood/osb.

Thanks @nod, yes priced is preferrable. I'm just trying the get a ballpark so I can assess how reasonably the overall price is, although it's going to be a multi visit job with a few hours of 1st fix and then 2nd fix work.

Given that they're like hens teeth right now, what's the going (reasonable) hourly rate to expect for plumbers in South West/ Bristol kind of region?

The Diathonite they used looks like an amazing product, but does it half cost, especially at 60-80mm thickness.

I know. After reading that other thread, I just couldn't help taking the wee ?? My sincere apologies, I'll close the door on my way out ? You're welcome. Yes there is something strange about sitting there all warm and then if you wave your arms about, they get cold.