Ian

Good choice!

Is that grade 304 or 316 stainless steel?

Thanks for that - I've never used blown cellulose before in walls and assumed it would need something more solid than just a membrane to retain it.

Won't you need an extra layer of OSB or plywood with the blown cellulose option?

@Ferdinand my new build 71sqM bungalow in Wales is now approx 1 year old. It's an EPC of C71. Heating is via bulk LPG. Its a holiday home so not really typical but the first full year of heating bills (Edit: inc cooking and hot water) came to about £170 of LPG which was 560 litres + the £60 standing charge for the tank rental. If I average the walls, roof and GF slab my U values are 0.15 and windows are 3G at 0.8. Air tightness is 3.7m3/(h.m2)

It's usually recommended to get any existing wiring above the new insulation

Make a phone call to the BCO and ask him what info he needs from you in order to issue his final completion certificate.

Have you made your application for Building Regulations approval yet?

Yes it looks very like wood to the point where they are very difficult to tell apart. The only real give-away is the lack of noise when you walk across the Karndean compared to real wood.

Traditionally you would be looking at cedar shingles if you wanted a timber roof. If instead of shingles you want to use cedar planks as a roof finish the timber will end up just being for 'decorative' purposes because you like the look of it. There will need to be a metal roof skin or plastic single ply membrane roof below with standing seams to which you fix timber battens to which in turn you fix your timber planks. Ive used this kind of roof build-up on several commercial builds but never with timber planking as the final finish. eg this roof system can easily be overlaid using timber planking: https://www.kingspan.com/gb/en-gb/products/insulated-panel-systems/roof-panel-systems/slate-tile-support-roof-panels-ks1000-ts

Try "caulking" https://en.m.wikipedia.org/wiki/Caulking

They are expensive and so there will almost certainly be a cheaper method of achieving the same end result using other products.

This kind of product maybe?: http://www.marmox.co.uk/products/thermoblock

The guy is clearly an idiot and is clearly out of his depth. To ask you to do that to a VCL shows his incompetence. As an architect I've been regularly dealing with BCOs in England and Wales for the last 30 years and I've only once or twice come across a story as bad as yours. Normally BCOs are very sensible people with a lot of common sense. (Scotland is a different matter as the system is still run by Local Authorities and the relevant departments are grossly understaffed.) If you feel the need to make a formal complaint the procedures are here: Code of Conduct link here (its a PDF) https://www.google.co.uk/search?q=code+of+conduct+for+approved+building+inspector&ie=utf-8&oe=utf-8&client=firefox-b&gfe_rd=cr&dcr=0&ei=VAUUWrn_EezR8geB_4qoCA Extract from document regarding competence: "2.4.1 An Approved Inspector shall ensure, prior to entering into an agreement for the provision of professional services, that the Approved Inspector has the necessary level of competence and experience required...." CIC complaints procedure: http://cic.org.uk/services/complaints.php

The basic principal of a VCL is that it should ideally be installed on the warmest side of the wall build-up so @MikeSharp01 is right that it would be best to have the VCL covering the PIR and then your battens to form the gap for your service zone and then the plasterboard. In my own self-build I didn't have a separate VCL layer - instead I taped the foil faced PIR boards together to form my vapour check layer.

You've got my sympathy - as an (English) architect I've also had the unfortunate experience in having to deal with the enormously frustrating, flawed and inefficient Building Warrant system in Scotland. For those Forum members not resident in Scotland its important to note that the system in England and Wales is very different and much less bureaucratic. You're allowed to start work on site 1 week after submitting notice to the BCO. The downside of the system in England and Wales is that the regs are sometimes treated in a more lax manner.

The easiest way to prove compliance with UK Building Regs is if the product has a BBA certificate. From my experience of dealing with building regulations in England and Wales since the system was taken out of the monopoly of Local Authorities, there is a vast difference in the approach that individual Approved Inspectors take. Some Approved Inspectors are 'by the book' and some are very flexible in their approach and open to the use of different approaches rather than strict compliance with the Approved Documents (as @JSHarris said the ADs are simply a short cut to compliance and are not the actual regulations). With my own self-build my BCO didn't even ask for details of the simple metal roofing (not standing seam) that I specified, although as it happened I wouldn't have specified a system that didn't have a BBA certificate.

@Russell griffiths What approvals are you going to need exactly? I would say that there's a bit more scope for the use of innovative or unusual materials within the Building Regs system than there is if you are having to satisfy the requirements of a warranty company or mortgage company surveyor, however when it comes down to it I'd agree with @curlewhouse - the only way of guaranteeing compliance is to appoint your BCO early on in the design process and then open a dialogue with them about the materials you would like to use. Normally it doesn't cost any extra to appoint a BCO early in the process but I'd be upfront with them if you think that you will need a lot of input from them at the design stage - after all you will need their cooperation in the process and if they haven't budgeted for the required time they may not work with you in the way that you need.

@Russell griffiths A couple of extra thoughts with regard to metal roof sheets is to - make sure you design the roof so that you can span from ridge to eaves using a single sheet to avoid the potential corrosion and leak issue inherent in trying to joint the roof sheets mid-span. - penetrations through the metal roof sheets for things like flues and vents can be awkward to detail and construct properly so best avoided if at all possible.

Its mainly just gutters made from the basic colorcoated steel that I have an issue with. Its based on years of experience of specifying the product on large scale commercial buildings and also occasions when I've been asked to inspect buildings with earlier versions of this colorcoated steel system. (The corrosion protection of the current colorcoat system is better than previous versions manufactured back in the days of Corus and British Steel.) The failure points with the system are the cut edges and the gutters. I would say it's a generally a good product with the following exceptions: - I wouldn't use it at all in locations with very aggressive environments such as right next to the coast or next to heavy industry (in those areas you're better designing the building with no sheltered overhangs as these can induce poultice corrosion in areas not washed by rainwater). There are much better alternatives for these kind of aggressive environmental conditions rather than painted steel. - unlined gutters made of the material usually have the high grade paint on the outside and the thin low grade paint on the inner surface of the gutter - I've seen lots of gutters made from this material where the constant drip of water from the roof onto the gutter has lead to early failure. The gutter needs painting with something more protective or lining.

Hi Pete, What material are the gutters made out of? If it's exactly the same material as the colorcoated steel then they will need lining or painting as the base material is not ideally suited for use as guttering. The constant drip of oxygenated water from the standing seam roof onto the same areas of the coated steel of the gutter causes premature failure of the gutter. Ian

Our PP doesn't show fencing nevertheless we claimed the Vat back successfully on 150M of post & wire fencing materials + 2 large timber gates and gateposts.

That's the same specification as the slab on our new build. It's been down for 18 months with no issues. Our EPS 70 is 300mm thick - it carries no load apart from the weight of the 100mm conc slab.

Quote from Part B of the Building Regs: 5.5 Where a door is provided between a dwellinghouse and the garage, the floor of the garage should be laid to fall to allow fuel spills to flow away from the door to the outside. Alternatively, the door opening should be positioned at least 100mm above garage floor level.

If you want to comply with the British Standard then your roof battens really should be pressure treated with preservative. The BS isn't a legal requirement however your BCO may require compliance with it and any kind of mortgage or warranty surveyor will normally require compliance. Edit: I've just realised this is only for your Piggery!