Temp

I would be tempted to make the door reveal several inches wider than the door sill and run the breather and cladding down the reveal to below the sill ( same level as the rest of the building). Leave a 1" gap at each end of the sill so it doesn't have to be sealed against the reveal.

It appears everyone is parked wheels on the pavement both sides. Would the road be too narrow for an ambulance or fire engine if cars parked fully on the road both sides? That might be an argument for making one whole side of the road no parking? But that would make you really popular. Pavement parking is illegal in London but elsewhere the rules are mixed. I suppose it might give police/Council the power to move the car when they otherwise cant?

Many of us have got an elderly disabled relative. Perhaps ask council if they can yellow line a short section so you can access your driveway when your elderly relative is staying... https://www.honestjohn.co.uk/askhj/answer/128671/is-it-possible-to-ask-to-get-double-yellow-lines-painted-outside-our-house-to-stop-inconsiderate

Yes you can run the boiler flow temperature hotter than 60C. Perhaps test carefully to ensure the system cannot send a pulse of very hot water into the tub when it starts up?

A. i) Not sure. ii) I would expect it to deliver close to 28kW. Even when the return is 40 and the flow 60C. That's also a 20C uplift. But I think you should check the data. I might be wrong. iii) yes. Corrosion inhibitor in the tub water? B. i) Google suggests heat exchangers are about 90% efficient so you won't quite get 28kW out if you put 28kW into a heat exchanger. ii) I looked at the 30kW heat exchanger here... https://heatpumps4pools.com/myfiles/file/Elecro-G2-heat-exchanger-Leaflet.pdf It has a table for the power transfer vs delta T.. If your boiler is 60C and the tub at 40C the delta is 20C. The data for that exchanger says the power transfer is in the range 11kW to 15kW. If your boiler is 60C and the tub at 20C the delta is 40C. The data for that exchanger says the power transfer is in the range 20kW to 26kW. Perhaps use a bigger heat exchanger? iii) I think once the tub is upto 40C the boiler return will be too hot for condensing. C. If we assumed the heat exchanger power transfer was a constant 15kW thats 15kJ per second. To raise the temperature from 5C to 40C requires 35*1000*4200 = 147MJ. That would take 147*10^6/15*10^3 = 9800 seconds or about 2h 45 min. 147MJ is about 40.8 KWh (units) not including losses due to efficiency of boiler and heat exchanger, pipes etc. I'm not a boiler engineer! This is just physics to me.

Should be fine. The compaction of the soil is because invariably there are some spots that are soft because you had to dig or rake to get it level.

No rainwater down pipes you can connect into? What is the soil type? Do soakaway work on your soil? A French drain used as a soakaway on the patio side of the wall would need to be rather deep. Not sure it's a good idea so close to the retaining wall founds? We used a linear drain but we have drains it could connect into. You can put MOT 1 straight onto compacted soil. I'd go for about 150mm, 200mm better. Compact soil first, then compact the Mot in at least two layers. We hired a wacker plate.

Yes very likely the mechanism will drop in to the wall if it's like ours. Time to find out if those tiles are still available 🙂

Looks like we might get an interest rate cut August. Possibly sooner but unlikely. I want to see the government follow Biden and introduce incentives for manufacturing to move to the UK.

Are you worried about smells? Are you on soakaway or combined sewer?

I don't think we have any either. Our 80mm metal down pipes go via a rubber adaptor into 110mm pipe and a bend. We have a lot of trees that shed leaves into the guttering but and they haven't caused any issues. You can get things like this.. https://www.screwfix.com/p/floplast-d94-debris-gully/25121?tc=BT2&ds_kid=92700020953276340&ds_rl=1241687&ds_rl=1245250&ds_rl=1249404&ds_rl=1249799&ds_rl=1245250&ds_rl=1249481&gclid=Cj0KCQjw4s7qBRCzARIsAImcAxaVytNqcb5qpVfHvF3QwruB7T-FnMA0fGLkM3Dqpf-rO7xqhaoy6vUaAguUEALw_wcB&gclsrc=aw.ds Edit: I don't think they have a trap, they are just sealed to stop debris on the ground getting in.

You will need to ask the planners what constitutes starting development. Normally they expect you to have dug foundations and had them inspected by the BCO but I suspect this is so they have some record of work having been done. Planning law doesn't require that, it just say development must have started. The definition of what counts as development is open to interpretation. It's quite possible the planners won't tell you what you need to do or give you any confirmation that you have done it. Officially the only way is to do something and apply for a certificate of lawfulness/development on the grounds that work has started. I've seen this done for a wind farm they don't want to build yet. They build a short length of an access road and apply for a certificate.

If you want to continue with a floor 0.5m down then you are essentially trying to build a basement. You need to read up on basement design and construction, external tanking systems etc. I think I would lay a slab across the whole site rather than use trench foundations. External tanking is very dependent on good workmanship. It's important to do a good job of the fillet seal where the blocks meet the foundation slab. You can't just slap some liquid sealer over whatever mud has found its way onto the top of the slab.

Perhaps check if the glass would need to be changed? There are complex rules on glass below a certain height needs to be toughened glass. I forget the details.

You can avoid needing planning permission by ensuring any run off from impermeable surfaces is handled on site. Eg by draining towards flower beds or drains and soakaway.

They may want you to prove you have a right to install a mirror.

I'd design out all edging so the mover can cut right to the edge. Unless you like using a strimmer.

I'm thinking you need to reduce the width of the bottom slate so it's no wider than the door then replace the membrane and cladding either side of the door so it extends lower down to match the rest of the build. But I'm not sure how to deal with the door frame. The waterproofing should be done behind the frame/cladding with ventilation at the bottom so the end grain isn't standing in water. I allowed about an inch on mine.

I just wrote back to the address on the letter and told them we wernt complete and gave them an estimate of when we would be. They sent back a revised letter.

The former can be easier. Typically each bathroom has a "stack" which is a vertical 110mm pipe in a corner. Pipes for the WC, shower and basin connect into this. The bottom of the stack under ground has a large radius vertical bend. The top of the stack either goes up through the roof and is vented to the outside or it terminates on the inside with an Air Admittance Valve. The AAV stops fast flowing water in the pipework sucking water out of the shower or WC trap. For rooms on the ground floor we sometimes run one 110mm pipe direct to the WC. 40/50mm pipes go out through a wall into a gulley. The challenge for this approach is getting the 110mm pipe for the WC in the right place. If it's too close to the wall the toilet seat might not stay up. If you want a walk in shower (or no plinth under it) special care and planning is needed when laying the slab.

Can't you rotate the supplied 90 so it points down and to the side. Then you just need another 90 degree bend.

That might be risky. Its not uncommon for planners to grant permission for a conversion but refuse a knock down and rebuild. I know that's not what you have done but it can invite a closer inspection from the planners. I would try asking the BCO for a letter confirming that "I have issued a certificate for a new build because you have carried out your conversion to new build standards". Something like that. If he won't give you such a letter I would write a cover letter to the VAT man explaining that its definitely a conversion as per your planning permission despite what the Building Control Completion Certificate states.

Ground anchors.. might be cheaper elsewhere? https://www.amazon.co.uk/Ground-Anchor-Heavy-Trampolines-Anchoring/dp/B0BRTTCZXW/ref=asc_df_B0BRTTCZXW/?tag=googshopuk-21&linkCode=df0&hvadid=658855764650&hvpos=&hvnetw=g&hvrand=15985417671135510135&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=9045888&hvtargid=pla-2195966870085&psc=1&mcid=50cb5f09417a3df788aaba711c0c104a

If they are all the same it was probably original. I asked because if it was a more recent extension it might affect permitted development rights.

Has the house already had a rear extension since it was built?