Gordo

Any feedback on how it performs would be appreciated

the boiler is only about 10 years old. it has quite some life left in it yet. I hear grant will be coming in next year or two so just planning a head. I didnt want to over size the pump as the average temperature is around 7 degrees. dont know much about frosting up, so ill have to research that end. Does an oversized ASHP frost up less?

yes N. Ireland. i have historical data for past few years which show it rarely goes below 0. So if i have the option i will design for 0 degrees, but suspect MCS engineer would refuse to do that. MCS state design for -1.5 degrees for Belfast. in the few days it goes below 0 degrees im happy to fire up the stove.

would you mind looking at your data label on UDHWC and let me know the Kw rating of primary heating coil for comparison.

I hear you and agree if tank was old id replace. but at £1500 the payback would be unrealistic. Heating with immersion works out at around £255 PA. if the heat pump managed a COP of say 2.5 id save say £102 PA with a payback of over 15 years if i replaced tank. I guess what Im wondering is if a 5Kwh heat pump could heat my existing tank with its 16Kw coil? I assume the 16Kw is based on a flow temp of say 60 degrees. Most HPs can manage 60 degrees but probably not with a good COP. Maybe im ignorant but id assume 5Kwh DHW load with 16Kw coil at 60 degrees would give theoretical a heat recovery in the region of 30 minutes now. From experience that bears out now. But if i fit a 5Kwh heat pump that obviously changes. Surley the heat power from HP would be say 2.5Kwh maybe at 60 degrees (maybe this is silly thinking and it remains at 5Kwh with more electric consumption). This would mean a reheat time of say 2 hours at 2.5Kwh (or 1hr at 5kwh) at around 60 degrees. I assume the HP reduces the flow rate automatically to achieve the set 60 degrees. maybe iv got it all wrong. help i need educating

I am considering a ASHP to replace my pellet boiler. I have done space heating heat loss calculations that indicate a peak load of 4.7Kwh at -1.5 degrees outside. So aiming at at 5Kwh heat pump. I have a pretty new 200l UDHWC with a 16kw / 0.7m2 primary heating coil which i am reluctant to dump. if using the pellet boiler to heat it i have to close off gate valve to tank to almost closed because the DHW demand is so great. I generally heat tank with immersion heater at night on E7 or with solar in summer and use about 2-6Kwh per night as it works out cheaper. I think i would be a loooooong time payback on new HP tank so would prefer to keep my tank and heat it with the HP. Has anyone got any advice for me please?

The first plan of stair with landing tapered would comply with B Regs. Maybe not so pretty tho. The 1/4 landing mentioned by someone would have a single step at top which wouldn't comply.

Fixed price all the way. Time and materials contract will spiral out of control fast. Unless you can financially incentivise the project manager to meet targets. say basic weekly wage for PM and then a bonus for meeting targets like meeting cost, time and quality targets. I don’t know how you would set such targets without professional advice from a QS. Be very careful not to allow contractor/PM to load payments towards the early payment. I have seen some horror stories Where PM has been given too much scope basically stealing materials and defrauding his client. Don't do it unless you are actively involved and very careful and remain suspicious/vigilant

Don’t do it like this. It would be a bodge job. The company’s who upgrade conservatory roof have had structural engineers advice and from experience have to load test the completed roof to measure deflection in window frames to get BC approval. even then I don’t like it. Often the foundations and floors are substandard. I’d suggest tumble it and start again as safest route.

I agree. Grout it. The small crevices will hold water and you will have lime scale and mould even if your substrate isn’t soaking. Not worth the risk

Oh ? I thought he mentioned SIP panels roof under EPDM and your last post here discussed a warm roof. In that case and it’s a cold deck roof ignore all I said ? But advice stands if it’s a wam deck roof.

How long is piece of string? Cost depends a lot on where you are located and how high your specifications are. Knocking it down and disposal won’t be the main cost it’s the rebuild. Any budget cost I would quote you are likely to be irrelevant.

The cold timber deck between EPDM and insulation will be vulnerable to decay there is no doubt. To do this properly their should be a ventilated void between the deck and the insulation in your second option. You have been warned ? impermeable weatherproofing layers are usually laid direct onto rigid insulation from my experience. No issue with walking on insulation doing this?

That explains sprinkler system. Three storey now & open plan GFL so no protected stair. All the same “no one has ever died in a building with a sprinkler system” stands but may not be code compliant.

With a sprinkler system who needs fire doors. No one has EVER died from fire in a building fitted with a sprinkler system.