George

Yes you only need to insulate the external thermal line. If the lean to isn't insulated or a habitable space and is effectively ambient air temperature then you should treat the house wall as the 'outside' and ideally insulate all the way to the ground. However, any lean to does create some level of protection so would need to be judged on a case by case basis. As you have shown, you need to go beyond the actual join point of, say, 600mm, (or the distance of the wall which gives an equivalent u-value).

There are two types of load bearing - vertical load bearing and providing horizontal stability. B For vertical load bearing the best you can do is educated guesses until you remove the plaster in the wall and ceiling and see whether anything is sat on top of the wall. The toilet/utility wall - From the floor plan it is unlikely to be vertically load bearing or providing buttress to the main exterior wall. However the dining room probably is both vertically load bearing and providing a buttress to the long side wall. You may need to leave a 550mm buttress in place or insert a wind post. I question why you as a landlord are doing this on request from a tenant. If they didn't like it as was they shouldn't have rented it. Unless this will add value (I don't think it will) to the house, why do it?

Plans and drawings for planning permissions are straight forward enough. You can look at what others have submitted in the local area to get an idea of what they should look like and contain. Structural plans and building control details require more background knowledge.

I wouldn't send my main dwg file - there's too much work in progress and standard details that get dragged into every drawing file. But I'd certainly be happy to send out a purged version.

I've seen pallets of blocks go through beam and block flooring so be wary. The domestic live load the b&b will have been designed for is 1.5kN/sqm so you'd be safe storing 150kg/sqm on them if needed. A pallet of blocks is more like 1000kg, or 700kg/sqm.

A fellow freelancer engineer! Legally you don't need insurance, or to be Chartered (but you must not describe yourself as a Chartered Engineer/Chartered Civil Engineer/Charter Structural Engineer or, I think, as a Professional Engineer). The ICE Code of Conduct does state you should make clients aware of your insurance situation - whether you have it and its limits. But as a sole trader all of your assets are at risk if you were to be sued. Professional indemnity insurance gives you some level of protection as it should provide legal cover and would pay out if you had made a mistake but you had used reasonable skill and care. While I have never had any problems with my designs, if you deal with contractors (as opposed to homeowners and the likes who use this forum), there is a chance you get caught up in the litigation mess if a project goes wrong. Even if nothing comes of it, there can be substantial bills. As I am Chartered and not getting involved in high risk construction (basements, cladding design, underpinning) then PI is relatively cheap. I have recently established a limited company. I don't look for work on here because I like to have local jobs - if you don't visit site then you don't know (although I did make exceptions during the pandemic). If anything, registering for VAT if you don't do much business to business work may work against you. As I am usually instructed by an individual and I'm below the threshold, I haven't registered for VAT. But I can 'afford' to stay under the threshold because I also have another job. Most importantly is to apply the code of conduct of the ICE, even if you aren't Chartered - know your limits and deal honestly. The problems I have seen over the years is when people get into something they didn't really understand or didn't thoroughly check. Edit - also, ensure you know the CDM 2015 Regulations and your duties under it.

Thanks - that all seems to back up my rudimentary understanding, which could be summarised as: Single dwelling house of 2 stories (<11m) = 30min fire protection to elements which hold up floors, walls or escape routes. Fire protection to roofs not necessary. I suppose the question is, does the dormer class as a wall, or is there further structural support offered by the roof which would warrant fire protection?

Sounds unnecessary based on my rudimentary knowledge. You may need to get building control advice, though.

With ICF you aren't tied to the Part A rules on masonry wall openings. Although they will still give good rules to follow for basic layouts that will work comfortable. The manufacturer would need to explicitly be providing you with a design which demonstrates compliance with the Building Regulations (via use of the appropriate British Standard or Eurocode). If they cannot do this then you will need to get your own structural engineer to get the design to comply. They are also unlikely to comment on or design foundations, aside from giving take down loads.

Sand and gravel over there. BGS Engineering geology https://mapapps2.bgs.ac.uk/geoindex/home.html

Makes you wonder how much liability building control carry for this compared to the insurance company. Many homeowners don't want to shell out £1200 for a ground investigation report (especially for an extension), so it's all done on best guesses. Edit - Oxford has 'High' volume change potential clay. So it's not an unknown risk.

If the ground is good and the foundations were put in at the correct depth then I wouldn't worry. If there are issues in future you could crack stitch the masonry to give it more continuity strength.

I'm not sure 3x2 (75x50 mm nom) should even be spanning 2m. TRADA tables says 1.24m for a C16 47x72mm. That said, light storage is usually OK. No books!

1) yes on my consumer unit. It matches fairly well (within a few percent) of the Samsun controller. 2) I've it set at 50C with priority. The tank temperature gauge varies between 43 - 55 depending on what's being used and if the ASHP is heating. The disinfection cycle using the immersion that takes it up to 60C is very notable on a Tuesday morning. So... works as expected.

It will depend on where the other flues are located. Have you got any photos to upload? Building control should be done and they may want a SE to look at it, although it is unlikely.

The nicely demonstrates how houses are just piles of bricks stacked (not glued) together. Mortar has no reliable tensile strength - once it cracks it can be lifted off. But gravity is effective at keeping them in place.

CDM2015 does apply to projects with domestic clients - it just transfer all duties onto others. CDM2015 doesn't apply to self-builders because they are doing the work DIY (so there is no 'work' activity, so no Health and Safety at Work Act 1974, so no CDM2015). If it is no longer DIY (for example, employing other (sub)contractors and they manage the site), then they become the Principal Contractor and CDM2015 does apply. The duties under CDM2015 aren't onerous, so it's best to apply them so it doesn't become a panic later on. Decent Welfare, a written plan, keep things safe.

It depends on the project as to whether it is simple or not! Sometimes things that appear simple I know will be a headache and price accordingly - I also never like to diminish the architectural ambition if at all possible. I would only do drawings which are suitable for Part A of the Building Regulations and for the builder to know what structural member needs to go where. I would not routinely include information that relates to the other parts of the regs - insulation, acoustics, ventilation, access, even fire I only know in detail for structural fire protection. (I'm experienced in drainage design but I keep that as an extra service.) I also don't do setting out since a lot of the requirements of the building regulations are all about space (widths of corridors, head heights etc) - but of course I make sure any structural members will fit and coordinate as needed. A lot of those building regulations things you don't actually need to be on a drawing or done by a consultant. You could go to manufacturers and get u-values yourself and submit that. But if you want me to do that, and compile the information, I'd have to charge. Regular or pre-planned inspections is something I've never been asked to do on a domestic build - only called out in response to problems. I think I would do it, but it'd have to be ~£100 a visit to make it worth my while. It's also doubling up on the role of the Building Regulations inspector and they have statutory powers whereas I just have a report back to the Client. Hmmm... so what do I do? I design the structural members size/shape/connections/foundations for anything that can't be read straight from a catalogue or table. Even with a simple span table, I bring the underlying understanding to know whether it's the right choice. I do also always specify in standard structural products like lintels - but this is a trivial thing to do and is more for completeness.

As a jobbing SE, a lot of builds never need to pass under the nose of a SE. If they are built to building regulations standard arrangements, and the soil is known quantity with a reasonable degree of certainty by the local authority inspector, a SE doesn't add much. But anything that steps outside of the standard will need a design. As other's have said you're paying for three things really: skills/knowledge/experience overheads including professional indemnity insurance time to do the work Just looking at time ignores the first two major costs and investments the SE has made.

I don't think there would be a true trussed roof solution to this. They would certainly be able to come up with a solution but it'd be based on a similar system of beam supports. Worth enquiring but they'll need an accurate drawing with levels. There is, I think, enough structural information to build from (albeit messy and I wouldn't be happy issuing that - my entire career has been CAD based). But they have left you with significant practical challenges. You really need more setting out information from the architect, else the carpenter will need to set things out. I'd be tempted to set up a site meeting and knock some heads together.

I wouldn't try and compare timber to concrete. Just assess each opening on its own merits compared to the load rating of the lintel. The lintel manufacturer or a structural engineer can assist with this.

Photos and drawings... Architect should definitely have an idea of what the roof looks like. SE may or may not have it in their original scope - often with builds it's a trussed rafter which sits with the manufacturer to design (SE only to review/comment).

Probably a miscommunication or not aware of the product (trenchblocks aren't ubiquitous). I would accept 3.6N trenchblocks but I would not accept 3.6N standard blocks below DPC. It usually isn't a question of strength but durability. Is the SE clear they are proper trenchblocks?

It is better to keep the outer leaf up to floor level, this gives the cladding something to meet up with that won't rot and gives the telescopic vent somewhere to sit.

Longer bearing doesn't matter but for a normal sized window (not 4.9m + that is a proper opening), you are safe just adding 300mm. A few mm here or there shouldn't matter. The structural drawing should be highlighting where something is unusual or extra bearing is required.