George

This is the crux of the matter. I think I would have gone for two connected columns, each orientated for each portal frame - or as you say, not have a moment connected from B3 to C2 and rely on the C3/ C4 portal frame in the up/down direction. There's something of an ongoing debate in the structural engineering world about whether steel frames in extensions can rely on the stability of the existing building (if enough walls remain) or whether they need to be independently stable. I have tended to use the existing building where possible...

Nice one - managed to find that product individually. Got some other bits and bobs too.

It's not expensive but I can only find a 10 box for £55.

Ah yes, I thought it might be the key design element! Don't mind my opinion as I am a random on the internet, but for me, it doesn't fit well with the old building. Practically speaking, I have south facing bi-folds and the winter sun is a right pain, and I think you'll struggle to get blinds to protect you with that glass façade. The entrances makes more sense now although I'd still just keep the existing doorway if you want an entrance to the living room. You may tell I also subscribe to Period Property forum!

Apologies for making a topic just for a single question, did a search but can't find a decent answer. Sealing PVC ductwork... taking a look at the data sheets for the proprietary duct sealant products (e.g. Soudaduct), they just appears to be decorators caulk, with a little more flex. Has anyone just used caulk instead? In a domestic set up I can't imagine the sealant is under very much pressure. I would also be taping. Alternatively I could use general purpose silicone, which will seal anything.

Personally, I think the big glass box detracts from the old farmhouse. Which way is south? You might have sun streaming in and blinding you when trying to eat dinner/breakfast. Is the main entrance into the glass box or the living room? If possible, you could swap the hall and living room, retain the original front door (build a porch as well), but bring the stairs pretty much up the same place. The kitchen units look a bit small, but depends how much you like cooking. You have 5 external doors but not sure there's a logical practical one... although I live on a working farm so priorities a bit different... I have muddy boots off, somewhere to wash hands, hang up coats, then into the kitchen. I also have a 'formal' entrance (the original old house entrance porch) and a side entrance from kitchen to patio. Obviously this is a bigger house so the other gym/side entrance does make sense. It's the glass box and living room entrances next to each other that don't make as much sense to me.

I would go for a sealed/polished concrete floor (or tiled) and leave the ICF blocks alone. It would create a lot of waste and the finish on the EPS would be.... uneven to say the least. Plus you'd have issues with dusting, fitting furniture in etc. As I understand it, the MVHR won't remove heat as such, but if you place the intake on the north face the summer bypass mode will help. A low u-value will help prevent overheating if you prevent a warm air getting in and solar gain. (Worst comes to worst you could fit an air conditioning system running on PV) So a brise soleil or awnings are probably your best bet - personally I'd go for a fixed brise soleil if it suits the building, because you know you will need to shade and you're not preventing any winter sun by the sound of it. Also, openable rooflights will allow for a lot of ventilation.

Structural engineering isn't rocket science... but you need to work out the loads the beam is taking, the bending, shear and deflection that will occur for a given beam size/material, have it comply with Eurocodes/British Standards and Building Regulations, then check what it is sitting on is strong enough, and ensure that the overall stability of the building isn't being compromised. I wish there were a single table I could use to look that up! Connections are clever/complex (I used to be a bridge engineer where all connections are definitely designed by the SE!) but the forces involved in buildings are pretty low so standardised connections are fine and most fabricators want to detail them themselves, so I don't offer it as a service.

It depends on the scale... if it's one connection then I'll just draw it up using the SCI detail. If it's a frame, then it just isn't worth my time. Connections have a bearing on fabrication and erection and that sits firmly with the steelworker.

I'm a SE and I don't design steelwork connections unless they're very unusual. It really isn't worth my time or the client's money because a fabricator will want to put the connection together in a manner which may not work with my design. ALso, most connections are just looked up in the SCI books (the green book) and need no input from an SE. If they're any sort of fabricator, they should be used to detailing connections to suit the forces and type shown by the SE. As I don't do them often, I'd have to charge ~50% more fee for the design of a steel frame if I was expected to include detailed connection drawings.

What the building is made from (as opposed to looks like) doesn't matter from a planning perspective, and they were probably wise not to get too bogged down in details when their fee only covered planning! Recognise there will be a real cost in order to get the other architect up to speed, but your money so far bought you planning, so there's no reason not to shop around for the next Stage. No recommendation in regards to ICF builds I'm afraid. I'm researching them now from an SE point of view as I would like to move towards more sustainable building techniques.

PIR insulation should be above the DPM anyway. Only time it's a concern in the floor is during concrete curing - wise to tape or stick some polythene over the top to protect the insulation for the ~24 hours of initial cure time.

There is probably bed joint reinforcement above the arch, forms a type of masonry beam. Impossible to tell without construction drawings or some fancy metal detector.

You have a point about the lounge area, but open plan kitchen and dining area is a function of the changed role of women in society and how cooking is now a common social activity. No longer are meals prepared in another room out of sight and brought into the dining area, because the chef wants to be part of the hub. I see it as a societal evolution rather than a fad. Certainly has been around a while.

The architectural proposal minimises cold bridging, but are (or can be made to be) equivalent on waterproofing and a low risk for condensation. It is not optional to chose an architectural suggestion over a SE design as it is the structural load path in question.

Most likely the primary reason is the lack of ties. Structural walls must have minimum thicknesses for building regulation compliance and, more importantly, a slender blockwork wall has a much reduced load bearing capacity. Another solution could be developed, I'm sure. But I wouldn't worry too much about small thermal bridges - you might be able to sit the beam and block onto foam glass blocks to minimise the thermal bridge and use 25mm PIR boards to wrap around any potential cold spots.

Licenced waste carrier that can take hazardous waste, I think you can check here: https://environment.data.gov.uk/public-register/view/search-waste-carriers-brokers You need to do all that is reasonable and practicable to check it is legal. So record the emails/phonecalls that you have had to demonstrate your due diligence.

The innerleaf is a good idea, there are systems which rely in on wibbly plastic lining which create a small cavity for any penetrating water to go through - but with the floor above to be supported, it's a decent solution*. I assume you are also tanking the outside of the concrete, but it is essential to have 2 waterproofing system and the internal lining is the most robust (especially for smaller builders/contractors). There are a few structural reasons why the SE may wish the floor to be supported off the concrete: - to keep a waterproof lining, there are no wall ties back to the concrete so that the blockwork alone is too slender to support the floor (a normal beam and block support on blockwork is only 2 courses high, not ~7 or 8 courses) - the blockwork specified is not strong enough - floor is providing restraint to the top of the concrete wall - doesn't want a line load on the retaining wall foundation as it will require increasing the size of the wall If those are not problems for the SE then I cannot see a reason for it not be supported on the blockwork as per the architect. I would suggest offering more fee for them to adapt the design but avoid steelwork, as this may need to be galvanised. *If you end up not using the blockwork, you get rid of it and look for a cheaper lining system Edit - you cannot disregard the SE opinion, by the way. You must use the SE option at the moment!

I'm 75% the way through installing MVHR (radial ducting in, just need final runs from manifold and to the roof). Can't switch it on yet as still plodding away on the inside. I did consider an alternative plan of installing a positive input ventilation in the loft, plus 3No single room MVHR extractors (2x bathroom and kitchen). In hindsight, this probably was a better solution but I am hopeful the whole house system is worth it. ROI is less of a concern due to wanting to resolve damp (normal old house damp, nothing dramatic) and air quality.

Depends what Mira shower you have, over 20 minutes could definitely use it up... could be up to ~15 l/minute With ASHP, presumably running close to 100% hot water usage with minimal cold water mixing. I think the break even between a bath and a shower is around 10 minutes, at most 15 minutes.

Oh that's good to know - it's a Gen6 Samsung EHS so it is bang up to date and I hear it ramping up and down so the inverter control is doing something. I'll certainly keep tracking COP - only have the on board generation calculation to go on, and the secondary energy meter to check against for usage.

It'd be worth talking it through with a system designer, as it depends a lot on the target temperature. So long as a room doesn't lose more energy than you put in, any size rad can heat a room - just needs to start a few hours earlier. If you could have a 2 zone system, with the upstairs running with a lower target temperature on it's own thermostat, so the smaller rads would be less of a problem. Depends what you have now, really. I installed a whole new system and some of the rads are pretty big, but no wider than the windows. They're just double depth. But if you don't need fancy rads, you can get virtually any size you want.

I don't know whether you fixed this but I had the same error. Immersion needs to cycle up to 60 degrees to kill off any bugs once a week. My problem was the HWC thermostat had been knocked a bit so kept reading a lower temperature than it should have. I poked it in a bit further and taped it in place. Has been fine (and got a jump in COP as presumably the heat pump had kept overheating the HWC trying to get to stay at 50 degrees which is the normal target temp).

It's all about trends, and the trend is a rapid decarbonising of the grid. Yes we'll be using fossil fuels for a while yet, but less and less every year.

You shouldn't need a back up boiler - when installed in the past they were only meant for taking over from the ASHP when temperatures drop too low. This is not really a problem now, although the efficiency does drop significantly. It sounds like you want a part fossil fuel and heat pump system.This means you will have reduced RHI payments as only the heat pump heating/DHW is eligible. You would need to submit meter readings as it can't be based on the EPC/heat loss calculation. If you are worried about only heating water when needed, the HWCs are highly insulated so only lose a few degrees each day and you can spec even thicker insulation. It is quite efficient for an ASHP to heat a tank up as it doesn't need to cycle on and off, which can happen with space heating. I know oil prices are very very low right now, but when I calculated pre-Covid, the heat pump was considerably cheaper to heat water than fuel oil. Presumably over the next few years when aviation restarts, we'll see fuel oil return to a high price. I would use the money you would have spent on an oil boiler and do extra insulation or solar PV to offset electricity consumption.