Dave Jones

add another block to the inside skin and have a normal gutter. box gutters = ongoing maintenance every year, clearing moss/leaves. it wont be the architect who does that.

have you got MVHR or trickle vents ? ICF should be very good for no leakage would have thought. Whats your heating req in m2 in watts ? gut feeling is your 50% overspeccing the ashp. it should never have to run a defrost cycle if used properly. mine never has.

drill baby drill. Reform will sort.

remove all zoning controls (if any fitted), 8kw sounds very large, what do the heat loss calcs say the engineer has provided to you backing up his design of 8kw being required ?

i tried also, octopus refused without MCS cert. How did you manage it ?

the problem with self install is no MCS paperwork. Octopus wouldnt accept any export from me (for payment) without it.

thats a cold roof not a warm roof. warm roof has to be sealed and doesnt require ventilation. very difficult to achieve by insulating between rafters on the underside.

car charger (not a piece of paper) is a planning requirement for us. It has to be a proper charger not a socket.

we have 150 in our airtight place. adding the celotex as well would be pointless honestly. The heat pump spins 4 hours max overnight at -10c already. 250m2. save yourself a load of time and hassle and invest in better windows and doors.

did our last 2 builds on a notice. cheaper than paying an architect for plans that only BCO will look at and file. The flip side you need to know what your doing so not good for a noobie. At least you have the archi to blame/sue if it goes wrong.

existing is more of a challenge where there is none/not enough cavity insulation. Compromise is EWI with doggo render or smaller rooms and internal. Damp being major side effect of poor install would defiantly have networked decentralised MVHR units to take care of any potential issues where there is no room for ducting a normal system.

you wont pass building control inspection if your cold roof isnt correctly vented. The tyvec at ridge needs cutting out as it will be overlapped with dry kit for the ridge. eggboxes at eaves where cavity insulation is covered by loft roll etc. you can only get condensation if heat is escaping into the loft, 400mm min of loftroll everywhere and no probs. Forget using loft as storage.

put a dergo in as well. sign it off. remove vent pipe from roof. If you have a combined foul and grey sewer then the downpipes are venting it anyway although it doesnt appear to be an 'approved' method for reasons only understandable by building control.

they wont touch it. its a closed con shop the MCS system. They will want to have done all the work and charged you 5x the market rates.

out of curiosity why are you going down the #TF route ? Are you expecting to be fully complete in 3 months and move in ? speed seems to be the only factor in justifying its double the cost of a normal build.

have exactly the same. really wish I had ducted it. It would take some thought though as the duct would defiantly condensate and would need to go uphill at somepoint to connect to a external vent and there would be pooling of condensation with the associated smells.

wait , your warranty has not inspected your foundations ? what council is this ? Have you got your local coucillor on the case ?

worst of both worlds is what you have. solar heats the tank when its hot with pv divert, as usually when its really hot there's loads of sun. by 11am latest our 250L tank is 80C via solar diverter. as a bonus it spins the heat pump for free as well for cooling, at least for us with just under 4kw of pv on the roof. It's like buying an electric car and then a diesel car as well as its a faff charging on a long journey.

avoid the tongue and groove celotex like the plague. massive waste as it has to be cut when it comes to windows. brickies hate it taping nonsense every joint. dritherm 32 every time. no waste, bulletproof and superior install.

tail wagging the dog. work back from the invert of the manhole they connect into. That will define how deep they go.

MVHR will never be enough on its own to cool the house. I tried, even spent a large sum on a dedicated and useless MVHR chiller intake. As long as you have UFH AND fancoils in all the upstairs rooms you have free aircon. Windows should be closed as a default with MVHR anyway whoever had an issue with open windows.

worrying about nothing. why didnt digger have a laser is the bigger question.

nope. you get a QS down to the last nail including time line gantt etc second fix items of course are prov sums. its all automated, they turn around a set of drawings in 24 hours.

used the blauberg units on a friends house, very impressed with them. not cheap though. They can be 'meshed' together to provide cross ventilation if needed. Bathroom have different model than the living area versions to handle the moiusture. the kit is very good and provides for an air tight install. shame they are not MCS certified.

I did exact same as I didnt like the look of the little chimneys. Problem I had they are not big enough and throttled the air flow (MVHR complained about restricted air flow) so had to ditch the plan.