All Electric House & DEAP (SAP-UK)

[mike2016]

Hi,

I'm running into trouble trying to get a Willis Heater for underfloor and a central water heater (Siebert Eltron) approved by my Architect. They claim it won't meet Part L. I'll have 8 x PV panels and it's going to be a Passive House so my question is has anyone else had difficulty passing SAP / run foul of Parl L regs going all electric? I'm holding off on an ASHP for cost reasons plus difficulty integrating a SunAmp at build time I won't go into here. I plan to add it later!  

Anyway, I have a preliminary DEAP xml and when I change the heating options it doedn't thrown up any errors but maybe I'm not selecting the right options. I think the Architect is being cautious so before I go back I'd like to find out if this is possible / feasible. Thanks. 

 

[A_L]

Not totally familiar with Irish regs but I think they are substantially similar to U.K. On that basis it would be difficult to get an all electric house to have a Dwelling Emission Rate below the Target Emission Rate if no help from a heat pump and insulation levels around building regs values. It should be possible with PH levels of insulation/infiltration however.

[Gone West]

@mike2016 We have an all electric PH with SAP A95 and no PV, so it's certainly possible in England.

[Ed Davies]

Isn't there a thing about the assumed CO₂ intensity of grid electricity being brought down at some point soon? Sometime next spring? Don't remember. That'd make it easier to comply.

[mike2016]

Possibly Ed,  but should I build if there's a risk I could fail Part L compliance at the end? Our DEAP isn't updated in line with SAP, not sure how much they've diverged over the years. 

Peter - Great to hear it's POSSIBLE to build all electric which is a relief. I think I need an honest discussion with the Architect in the morning and see if this is regulations or DEAP issue - they claim I'll fail Part L which is a bit too vague when it'll cost me 10K + for the heating system they've recommended. 

[Guest Alphonsox]

We’re using an all electric system in a passive ish spec house with no PV Predicted SAP2009 is around A91. What heating system are they recommending for your build ?

 

[mike2016]

Ecodan ASHP, underfloor heating, two upstairs wet rads. I doubt I'm falling foul of Part L per se, it's the DEAP calcs where I might run into trouble. Plus if they tinker with the Deap package before the build is finished I might cross that line and fail certification! Still, for me this is the best approach - cheaper, simpler, can expand later....that's if I'm allowed. So,now I know it's possible in the UK, I'll ring a few energy advisors here in Ireland for their opinion. Cheers!

[Nickfromwales]

@TerryE Terry, did you get into any difficulties as you didn't have PV either? IIRC you are using economy electricity so would 'full-fat' peak rate electricity have played any part in failure to meet Part L?

 

For the benefit of the thread, @mike2016 and I have been discussing this via PM and the architect has stated, quote -

 

“Using electric base heaters for space and water will not meet Part L compliance of building regulations. It will also not meet Primary Energy Demand on the PHPP results tab. My advice is to propose in tender a small sized heat pump, that is what we need in any case, with underfloor heating in the ground level and towel rads on the upstairs wet rooms (or landing). We can make a decision at that point on what can be afforded and possible alternatives. “

 

End quote.

 

The bit in bold is my favourite bit.  

 

The mention of PHPP is the stick I believe, but it has been discussed to abandon the PHPP certification to attain a 'lower standard' to get the initial aforementioned system installed to get mike up and running with minimum initial outlay. 

[Nickfromwales]

IIRC the SA eDual is a high SAP rated appliance, so may get you off the hook vs the Steibel. Ask your assessor and maybe ring SA to see what points it gets ?

[mike2016]

I'm caught between a rock and a hard place - Part L's DEAP vs the lack of SunAmp installers in ROI who can sign off such an install to satisfy BCAR certification of compliance which I need to get the house built. Hence willis/eltron combo which any trademan can install and certify clearing the way for SunAmp or other post build. Another solution is to put in the Ecodan ASHP CO2 high temp and replace the stainless steel cylinder with a SunAmp post build somehow. 

I'm going to ring around one or two energy advisors today to see what they think. I'll have 2.4 kW of PV to offset CO2 intensity but I don't know DEAP well enough to model resistive loads accurately and present it back to the Architect. Hassle I don't need! 

Anyway, There's an answer to all this I'm sure, I'd just like what's in the final tender to be accurate and on budget as there is enough risk next year with Brexit.... 

Maybe I could heat the house and hot water with candles?!

[Triassic]

Have you talked to @AndyT about your problems, he might be able to help.

[Nickfromwales]

@JSHarris, what constitutes a SA registered installation? Im still none the wiser as to what you need to "be" to fit and commission a SA. Is it as simple as abide by the Manufacturers Installation Instructions? There's no G3 so apart from an electrician making off the power supply, what gives?

@le-cerveau how did you achieve this status? 

[Nickfromwales]

9 minutes ago, Triassic said:

Have you talked to @AndyT about your problems, he might be able to help.

Sadly, AndyT has recently contacted me to announce his retirement. He has subsequently handed in his notice and left SA. He's being missed already tbh  

 

 

 

[mike2016]

The Architect has very tight reins over the BCAR/Compliance certification and no builder / tradesman I've spoken to wants to install something they've never seen before. At this end of the tender process its very hard to have that conversation even. Again, the goal is to get the house built rather than put off prospective builders with what should be simple but unorthodox requirements. 

Sorry to hear about AndyT, that's a shock as he was always very helpful and is one of the main reasons I'm made keen on SunAmp! 

 

[le-cerveau]

7 minutes ago, Nickfromwales said:

@le-cerveau how did you achieve this status? 

My SA units were installed by SunAmp, though all the preparatory work was done by my plumber and electrician.

[Nickfromwales]

1 minute ago, mike2016 said:

The Architect has very tight reins over the BCAR/Compliance certification and no builder / tradesman I've spoken to wants to install something they've never seen before. At this end of the tender process its very hard to have that conversation even. Again, the goal is to get the house built rather than put off prospective builders with what should be simple but unorthodox requirements. 

Sorry to hear about AndyT, that's a shock as he was always very helpful and is one of the main reasons I'm made keen on SunAmp! 

 

The hot water version of the SA unit ( the eHw ) has one pipe in, one pipe out and a 3-core flex. If you can change the spare tire on your car you can fit one of those. 

[Nickfromwales]

3 minutes ago, mike2016 said:

Sorry to hear about AndyT, that's a shock as he was always very helpful and is one of the main reasons I'm made keen on SunAmp! 

Yes indeed, an ambassador I think they could ill afford to lose. I shall invite their sales director to participate and pick up any questions here, but I fear he's now a very busy chap !

[mike2016]

So I think I'll go to tender as the Architect suggests with an ASHP specification and at build time look at options. I'm not sure if this is the Architects way of tying my hands or not but will see what prices come back and if any are affordable and at build time look at budget again. At least then I'll have a builder onboard and can look at options at that point. 

There are passive houses that don't meet Part L in ROI, you just need the PH certification and to send in a letter! Good 'ol Ireland! 

Thanks everyone!

[Jeremy Harris]

2 hours ago, Nickfromwales said:

@JSHarris, what constitutes a SA registered installation? Im still none the wiser as to what you need to "be" to fit and commission a SA. Is it as simple as abide by the Manufacturers Installation Instructions? There's no G3 so apart from an electrician making off the power supply, what gives?

@le-cerveau how did you achieve this status? 

 

At the time, following a few phone calls and exchanges of emails, SA reached the conclusion that I was competent to install the unit myself.  Part of that was because I was the first to use a SAPV as a primary DHW system in a low energy house, so had a few discussions with their technical people about what I wanted, what the SAPV could deliver, and some of the details like feeding it with pre-heated water instead of from a cold main.  It was after those discussions, and me asking a few questions on the phone having read the draft MI's, that they agreed I could self-install.

 

There's no certification required, as long as you already have the circuit in place to connect the flex from the SA, as connecting to an existing FCU isn't Part P notifiable, and I already had the wiring in place for the immersion and PV diverter, all signed off from when the house was built.  The same goes for installing the UniQ eHW 9, (which is arriving today), although I need to add an additional FCU for the low power control circuitry.  Luckily I had a 20A DP isolator fitted for the hot water system supply, so I can add another FCU easily enough without falling foul of Part P (it counts as permitted work without requiring Part P sign off).