PeterW

Right.. so following the post where I put the planned controls and layouts I have been thinking about the ASHP temperature control mechanism for this. You can see from the schematic there are two pipe stats that are directly linked to the ASHP control box. In the ASHP instructions, this is used to regulate the water temperature in the system, and as I want 2 different temperatures then I need 2 stats. The unit is supplied with a standard Siemens RAM1 pipe stat which seemed ok until I checked the differential - 8K +/-3K...!!! So at 37c set point, I could get a range of 32-42c which seems a bit excessive. I am trying to keep this as "off the shelf" as possible, and looking at specs its clear that 4K differential is the norm on these things unless you go upwards of £35 per device. I can get down to about 2.5K with one of these Computherm Capilliary Stat which seem pretty good. ( @JSHarris didn't you use Computherm..?) but I'm still querying if it is "good enough". The house isn't passive by any stretch but will have good air-tightness and a well insulated roof, with a January heat load of around 1180KwH. Overshooting the 35c stat will only result in the buffer being warmer than needed as the UFH will be set to 32c flow. I could go with something such as one of the many £8 DTC-100 based controllers from China and get myself 0.5C differential control on the water temperature but I do wonder how the ASHP will cope with this, and what the benefit will be as there is 9m of pipe between the ASHP and the sensors. I'm not going down the custom code / build route on this but I'm trying to build the best "analog" system that I can without spending a fortune but I'm left questioning how good do I need to go..??

Ties for timber frame are screwed to the outer surface of either the timbers or the OSB if present. The screw and tie will cover any hole in the membrane. An external single skin of blockwork is not self supporting at 3m tall and is dangerous - it has to be tied back to the frame as even wind suction could pull it over. Do you have the full set of plans for the design ..??

You would need to ask them. The better way is to get the structural timber frame up first as you need to tie the two together and you can't do that from the inside.

It's not studwork, it's a timber frame. It has to be built as a structural element to the SE design which you need to get hold of. You can use steel dry lining profile where it's not load bearing.

It's a structural C16 100mm timber frame to SE design so I would expect its 100 x 50 C16 on something like 400 centres. Double sole and wall plate from that picture.

I hate to break it to you but the roof is sat on the inner skin, not the outer ... look how the blocks go up and through the roof joists in the design. The two rectangles with crosses at top and bottom are the sole and wall plates of the inner walls - are those supposed to be timber ..?? The roof joists sit on the wall plate and that transfers the weight through the frame to the sole plate , not the outer skin. Suggest you speak to your SE about that detail as that is how I read it. To add : read the build up. Inner leaf C16 to SE design. That's a structural timber frame.

Mine insisted on 35/38 black smooth duct and as it was only 3m they even provided it for free ....

So are the structural brackets taking the load of the outer skin and the roof ..?? Have building control signed that design off ...??

If we had been able to drop the existing building and go for a full new build then they were my supplier of choice for this very reason - to be able to take a piece of ground from oversite to watertight in 2-3 weeks in the UK in February and March is just exceptional. Looks like quality and attention to detail is there, as is continual improvement of the product if things like the stud marking on the membrane is anything to go by.

So my bricky & labourer is about that for 2 days... And his quality is first class..! PM me if you're East Mids area ...

Got to say I'm with @Russell griffiths on this one. You need flat and straight blocks for render otherwise it will look odd - Brickies aren't too badly priced and it will pay dividends. Two days with a bit of setting out will get you probably 3-4 courses all round and you're away.

Meant to add the additional wiring is the link from HW Off to No.2 - this pushes the 3 way into heating mode when the HW is off

Looking at a standard 900x300 copper cylinder. I'm leaving the immersion in as that way it means if the ASHP ever fails I've got a big version of @TerryE Willis heater ..!

So this is mine less the PHE which I don't need. Buffer at 0.5Bar/atmospheric pressure. Use a 3 channel timer - one for DHW, one for buffer and one for circ pump and the stat to control the valve to the buffer. W-Plan modified to allow change over of the pipe stats needed to control the ASHP temp (47/35) And last one with power/neutral removed for clarity

Anyone bidding over 50p for his good looks may be disappointed anyway....

The Timeguard PIR switches from TLC allow you to remove the factory link and become volt free if you have a need for that on your MVHR.

£70 for a week to hire ...

Hi and welcome..! For Durisol @recoveringacademic is your man

I've had my delivery ....

Simple.... Two solenoids holding the rail onto its brackets - at sunrise the pins retract and the rail falls to the floor..... you have til sunset to reset it manually ...

Most of the new stuff is self cleaning glass anyway - in a single storey it's not too bad to reach either from the ground with a pole system.

It's a baby buffer tank that allows primary and secondary separation of flows. Need them on some boilers to ensure flow rates are maintained but not sure why you need one on an ASHP if you have a bypass valve as the heat input of an ASHP is nowhere close to the input of a boiler.

A lot of the self install pipes are precharged with refrigerant as they assume you don't have access to vacuum equipment to do a purge at install. You can just put soft copper pipes in and cap them off for future use but I wouldn't use a precharged pipe system

How many do you need ..? I got some really obscure bonnets from these guys - weren't cheap but then again neither are having handmade replacements made ..! http://www.jjreclamation.co.uk/product/marley/

Saw some at one of the shows (ideal home I think) and nearly fell over when they told us the price ... think it was Gliss and it was about £500 per rail ....