Big Jimbo

@Nickfromwales Thats exactly what i am doing

Hoping to start in about 2 month. should be better weather i hope.

I had planning to knock down an existing bungalow and build One new large house. I dug a small trench, and took a photo to make the application active. That permission had no requirement for a bat survey. My new application for Two new houses, which was passed, started mumbling about bats. I told ecology that the demolition was being undertaken under the big house application, and therefore the application for Two new houses had no requirement for a Bat survey. They were ok with that, and stopped muttering.

well as i am currently drilling deeply down into my fabric, and ventilation heat losses @SteamyTea . After completing my part "O". I am going to consider myself very skilled, but only when i get it bloody completed. I could murder a Kebab, or a bloody good burger, as my brian is currently using energy at a rapid rate.

My son in law works for a British, French, Belgium Company, that designs and manufacturers, and maintains weapons, missiles, including nukes. They do use a lot of American software, and hardware, and have begun designing this out. That makes a lot of sense to me. I hope we do have the ability to up our UK skill level. If we need a lighter, or a box of matches to make fire. We are buggered. The reason he says that they are moving away from US components, is that worlds buyers no longer trust the US, and want weapons that do not rely on either the US or China. He says that he doubts that the US will ever get the trust back. I'm sure that will have implications for them in the coming years. As he said, when he was in a previous industry, they used to send stuff to China to be produced because it was cheap. They used to basically steal all the R and D and re-badge it as there own technology. We still to this day, educate there people in our universities, to allow them to go home, and have the skills to do exactly that. America, is heading in the same direction. Can't be trusted, and thought of in the same way as China in the future.

I like that idea.

I think the concern must be the distance from the bottom of the window, to something solid below. Whether that is grass, patio, decking, etc. So he may be saying that at present the height does not comply, but it will however once yo fit your decking.

You could wedge a piece of pir across the cavity. Either 50 0r 100mm if you have room. Then your ply, then your wood flooring. That is providing that your new floor joist have all been extended over the cavity to support the ply.

Defo, best to try and find out from either the council, or there website. You don't want to fall foul of Cil.

I would have thought that you would be fine, the next day. You are only going to be drilling a few small holes.

The drawing seems to show a non ventilated flat roof on top of a cavity wall. There is no reason not to fill it all with mineral wool in my opinion. You should atleast fill it to above the cavity closer as that is a week point. You did well to find any detail for what to do as accepted practice. I couldn't find any for my funny detail bits.

I will have a talk to the estate agents today. I had a talk yesterday with a very well known guy in the industry who has a comprehensive understanding of heat pumps. For a fee he will take a look at my plans, do heat loss calcs from my drawings, and specs, to confirm my results. He will also design the system for me. If he cant fitit due to distance, i will atleast have a design that would enable me to have it fitted, with confidence, by a plumber that i know. I do think that a modern house, built with a bit of quality control (me) , and a relitively low heat loss (sub 5) is a great candidate for ASHP. I just want it done right first time, and for it to work with no problem. A bit like a gas boiler install. I just need to step away from my old flat cap, 63 year old self, and perhaps embrace the new. (not that ASHP systems are new). Just new to me who has always had an oversized gas boiler in all of the houses that i have ever lived in.

I have looked around locally, and spoken to two agents that i know well. Its felt that it is the best configuration for the local market. Nice master ensuite. double sink, double width shower. Bed 2 with small but functional en-suite. Beds 3 and 4 share a bathroom with separate bath and shower.

@Adrian Walker Also, i believe that at below 3 i would be required to fit MVHR. It is a shame but just really not got the space. I will have to have have 6 extractors for all the wet areas. I will have to have a look and consider what my options are on that front.

At 1750square foot, it is a compact 4 bedroom, 3 bathroom house. Although i have designed for 5ach, i will aim to be better. However, i don't really have room for the ducting for MVHR, or the actual unit. That and the roof pitch is shallow at 28 degrees. It's also a cold loft space, and i have a height restriction.

@Oz07 gas is already on site.

Fortunately a fair old distance away. However only a couple of hundred meters from One of the golfballs. Radar station about 50meters high. there are 3 or 4 around The outskirts of london. Used to track the planes into Heathrow. My weapons manufacturing son in law advises me that although not public knowledge, the stations are also used by the military. Apparently, that makes it on to the list of first of targets within the UK in the event of war. If that's the case i hope it's a nuke. I don't want to be hanging around. I'd rather be vapourised.

Thanks @JohnMo That's much more in my language. Thank you.

With regards the heat loss calcs, i am only doing roof and wall to current building regs, with block and beam floor and tripple glazed windows being slightly better. I do have a fair few windows, and my part "O" was a bit task to get a pass on the simplified version.

@JohnMo Thanks for your imput. I was hoping you would chip in. The total size is 1750 square foot. I believe i was dilligent when doing the heat loss calcs, but im happy to re-visit them. As for the other stuff you have stated, i will do some reading up. I'm afraid i'm a very practical guy, rather than an intelect. Old cars i can play with the mechanicals, and usually get things sorted. New cars with all the electronics. Not a chance. The main problem is having confidence in trusting someone else to design the system up, and unfortunately my previous expierience has not been great. I wouldn't even mind paying someone to design and pipe size etc. Just want to make sure i'm doing the best that i can Thanks again.

So in spring i will be starting the build of my first house. I have permission for two however, as i am going to have to borrow money commercially, (no income) . I will have to build and sell the first house, in order to provide the funds to build the second house for me to live in. Now i want to build a decent house, but not go over the top on spending as it will be sold. The house will be 1750square foot, 4bedroom, three bathroom. The ground floor is 94 square meters, and i intend fitting underfloor heating. The upstairs is 74 square meters and i intend fitting radiators. A water storage tank of 250 to 300l will be fitted to provide hot water. I have sized this to give the chance to have three 10min showers at the same time, with the water being stored at 45c. There will be One kitchen sink, One WC sink downstairs. Two of the bathrooms will be above the water tank, and the other will require a pipe run of about 10meters. The upstairs rads will be run from a manifold upstairs. I have done this in the passed twice with home made manifolds and it has worked well. The downstairs underfloor heating will be run from a manifold. I have as yet no idea re zones etc, but basically i will have a front sitting room, that i anticipate will be used mostly in the evening. a largish entrance hall. WC. Small laundry room. Study (where the hot water tank will be) and a large kitchen, dining family area. I have completed, what i believe to be a comprehensive heat loss calculation, and my result is a 5kw heat need. That was worked to 21 degrees inside, and -4 outside. I have even compensated for altitude, 150meters above Heathrow Airport. I have designed to an airleak score of 5, but hope to get nearer to 3. Obviously as a new build i have decent "U" values, and so a heat demand of 5kw seems decent ? I have been told that a 6kw heat pump would be fine, as long as i make sure i get One that can modulate down nice and low. I have been told that a gov grant of £7.5k is available via getting the kit i would need from a registered supplier ? Although i have gas on site, i'm keen to think about an ASHP. One of the reasons is that i have room on the roof for Aprox 10 solar panels South facing, And 10 West facing. I intend fitting these during the build while the scaffolding etc is up. I don't have the budget for fitting any battery storage, but intend getting the various wires run while the house is being built, so that they can be fitted with very little hassle in the future if wanted. I also have to fit an EV charger, although i dont have an electric car. Can anybody give me a bit of a steer if the above sounds ok? The biggest hold back i have is the internet being filled with people moaning about how ther heat pumps are rubbish. A local new estate has been built with heat pumps, and the moaning about cost, and lack of heat is all you hear from the people..... To top it off, i spoke to a heating engineer, who is actually a friend of that bloke Adam, from heat geak, and he said size everything for low temp running, make the install Heat pump ready, and stick a bloody gas boiler on the wall !!!!!!!! Any steer would be gratefully received. Regards Confused (Tired of being) and with far too many other things to get on with.

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I expect, but dont know, if the area behind the cladding will need to be ventilated, but i expect it will. So you will need to find something that leaves the gap free, usually 25mm, but expands to fill that gap in the event of a fire. Also, my own thoughts are that any cladding on the outside, should be ventilated, at the top, and the bottom, together with gaps in any battens that allow airflow into areas, such as under windows etc. Think of it as a roof that needs full ventilation. You could achieve full ventilation by using a cross batten system. Don't forget to mesh the top, and bottom to prevent, wasps, bees, mice etc, making a nice home behind your cladding. As for fire stops, in my opinion, don't be tempted to fully block the cavity, with fire socks, or you wont have any ventilation. I was pondering the same problem on a house that i didnt build in the end. Sorry, i could not find any products that would leave enough of the ventilation gap, and expand enough to close it, in the event of a fire.

My thoughts would bethat there may be some lime in there. I like the look if that is what you are going for. Best of luck with your build.

And there i was thinking you came from somewhere around Aylesbury. Don't know why.