WisteriaMews

If they've just asked for a warranty quote, rather than a proof of policy, hopefully you can just give them a quote. Similarly can you just give them a solicitors details, but tell the solicitor not to do any work until you give them the green light.

*penultimate bullet point should say "buy the new build warranty before you commence work...."

It would probably be best to speak to a self build mortgage broker as they'll be able to offer some advice on your circumstances (e.g. Buildstore - not recommending them, but they are one of the bigger players in the market). The Buildstore website has into on it how the process works too. Generically I'd say: - I'd hope you can get an in principle mortgage offer without having to pay any fees. - Knowing that the mortgage looks 'do able' depending on your approach to risk you could then get a QS / costing to price your build, to know if the house you want is achievable within the amount you can borrow. - if happy, press go on the mortgage. Conveyancing, mortgage fees, stamp duty etc.... all kick. The mortgage doesn't cover these. - Once you have the land, you need a bunch of professional services; architect, structural engineer, soil survey, discharging planning conditions, building control, etc... Your circumstances will determine how many of these you'll need (you can never avoid them all). I've not seen a self build mortgage that will release funds to cover these fees. - In my experience you need to buy the new build before you commence work (as they send an inspector as you go along). - Unfortunately there are lots of outgoings before you start building!

Currently planning for our next self build. We are doing to have an electric heated towel radiator in all the bathrooms and I'm looking for a controller to meet our two requirements: 1. Ability to set a schedule via WiFi / an app. 2. A physical boost button that we can press to turn the radiator on for an hour / two hours. For the times when you have a shower outside of the scheduled times and want to turn the radiator on to dry the towels by just pressing with a button and not needing to faff with a phone / tablet. Can anyone recommend a controller like this?

@TerryE thank you for the detailed reply. I'm not as IT savvy so the above is probably a bit advanced for me! 🙂 Might be a silly question, but how.did you install the top and bottom thermometers? I'm assuming they are on the outside of the tank? Did you try to get round the insulation to install them on the metal skin of the tank? It sounds like you only use a top temperature sensor to drive the boost if needed? Being able to have a boost is my main concern, so I might be able to do something simpler than your setup. (I'm planning to be on Go / Flux rather than Agile so will have a set block of off peak that I can just use a timer for.)

@TerryE @JanetE I'm looking to specify the same tank in my new passive self build, but have been struggling to find out many specifics about the controls. Ideally I think I'd like to: 1. Heat to full overnight on off peak electricity - it sounds like it has timers so this should be possible. 2. If the tank falls below a certain level boost it so there is enough hot water for evening showers / so we don't run out etc... - I haven't been able to find anything on a 'smart' feature like this being possible. Are you able to share your experience with the tank controls. Thanks.

PHPP tells us it's sufficient. Still feels like a bit of a leap of faith installing such a low power system.

Yes, our architects are Passive House qualified.

We're planning a certified passive house and are looking to install a Zhender ComfoAir Q450 with the Zhender Comfoclime bolt on that does heating and cooling. Assuming we hit the passive house standard, that should be sufficient for us. I see you mention above UFH (and also have seen your other post about ASHP), if you get a heat pump that can reverse you could do both via the UFH; heat the slab in winter and cool it in summer.

Not much further forward, currently waiting for the structural engineer to finish a few pieces before we can fully engage a timber frame suppliers. We're in London.

If you are happy with them, could you share who supplied your external blinds? I think we'll be installing some as well.

Thanks for all the info. We are looking at an Oso cylinder having seen it mentioned on the forum.

Our architects are doing the PHPP modelling so I'll ask them for the cooling load. We are currently aiming to be certified.

The MVHR design / modelling we've had done shows 229 m3/h or 286 m3/h on boost. The Zhender data sheet (thanks for the suggestion to double check all this) shows 1.1 kW of cooling at 315 m3/h, so we'd probably get ~1kW on boost. Possibly not enough..... What types of intervention do you use on hot days?

I'm pretty committed to getting a panelised system from an experienced passive house supplier. There are no experienced passive house builders near me, and I don't have a relationship with a building company who are committed to getting into passive houses / getting it right, so I see a panelised system as a lower risk option. We self built our current house and despite using a 'good' local builder, I've been disappointed with the thermal result (air tightness / thermal bridges). This has definitely influenced my decision for our next project.