Converting Attic Space In BER A2 House With Existing Solar PV Panels & Heat Recovery

sligoman2015

Hello

I am about to buy a new build Ber A2 house. Long story but only downside is rather small bedrooms so would like to convert attic space to 5th bedroom, with rear facing velux roof lights that do not require planning permission. I had an attic conversion done about 8 years ago so aware of various issues about adequate height/ habitable space as bedroom/ need for structural beams etc. Problem is that house has extensive solar PV panels on rear aspect and the house has a heat recovery system. Not sure where heat recovery unit unit itself is located (attic or hotpress), but the tubing must be going through the attic space for the existing bedrooms.

Two questions

1. Should or must the heat recovery system be extended to the attic space, and will the existing tubing get in the way of suspending the attic floor?

2. Solar PV panels- is it a big job to relocate them lower down on the rear (east) aspect, or even relocate them on the front (west) aspect? What about getting rid of them altogether? I have visions of a roof covered in leaky holes in the tiles if it is relocated! I imagine it is unlikely that I would get planning permission to put the velux roof lights on the front aspect which would solve this.

Thanks in advance for any advice/ help, sorry for being a bit waffly.

BryanF

1. Yes
1b. Site survey required
2. Define big job, I'm sure they can be moved to accommodate a roof light.
...
2b. Why would you not get planning?

sligoman2015

Thanks- would you care to speculate on cost of moving the PV panels to the front?
Re planning- I would have thought local authorities (fingal) were dead against front aspect vellum roofllights?

Strolling Bones

sligoman2015 wrote: »

Two questions

1. Should or must the heat recovery system be extended to the attic space, and will the existing tubing get in the way of suspending the attic floor?

2. Solar PV panels- is it a big job to relocate them lower down on the rear (east) aspect, or even relocate them on the front (west) aspect? What about getting rid of them altogether? I have visions of a roof covered in leaky holes in the tiles if it is relocated! I imagine it is unlikely that I would get planning permission to put the velux roof lights on the front aspect which would solve this.

Thanks in advance for any advice/ help, sorry for being a bit waffly.

1. All habitable spaces should be ventilated and it would make sense to extend the ventlation system into the extended space. I suppose you could ventilate it independently of the main system but that may then cause the existing sytem not to function properly. Frankly do not expect too much expert advice or experience with this as you will be one of the first wave in Ireland to look to modfy an A2 BER Rated house.

A well designed MVHR system will depend on optimal duct runs ( short as possible) so whilst it may be perfectly physically do - able to re route them "out of the way" you will make the ventilation sytem less efficient. This is not a fuel economy consideration - it is a health and safety consideration.

We need to start thinking of such high performance buildings more like machines than how we regard traditional buidings. Much more to it than meets the eye.

for instance - how will you identify and make continuous the air tightness measures ?

2. Any renewable energt installation is there to comply with building regulations. The roof orienatation and roof angle are part of a deatiled set of calculations necessary for building regulation compliance.

I don't say don't move them - I do say get a BER assesor to rerun the calcs first.

Ironically our newests houses share something in common with our oldest protected structure houses. They are not simple to alter. Legally.

sligoman2015

Thanks for your very detailed response. Re MVHR- seeing that I understand that it supplies air to bedroom spaces rather than extracting it, would it be feasible to just rely on window trickle vents in the attic space then?

Strolling Bones

The full term is whole house mechanical ventialtion with heat recovery. So the whole house air volume is taken into account and when comisioned it is balanced out. Air flows are measured at each inlet and outlet and ajdustmants are made to those airflow in order that the syetm works properly.

If I was doing this I would seek out the system installer and take their detailed advice.

sligoman2015

Strolling Bones- I know nothing about this area, so thanks for your expertise. Are you saying that once a new build has been bought by a private owner (me), you are not allowed to "downgrade" the BER rating? Presumably, say I buy a BER A2 house and stick on an attic conversion, and BER is thus downgraded to B2, this is my own lookout?

Strolling Bones

A more complicated question than you may think.

What you can't do , legally , is do something to your building to adversly affect your compliance with building regulations.
Like - weaken a structural beam or remove the disabled acess visitable toilet. Or move solar panels from one roof slope to another without checking Part L.

You could lessen your BER rating provided that you still complied with Part L of the building regulations and provided that when you go to sell or rent the house you had published with SEAI a revised BER Cert .

.

Strolling Bones

sligoman2015 wrote: »

Presumably, say I buy a BER A2 house and stick on an attic conversion, and BER is thus downgraded to B2, this is my own lookout?

To clarify it is possible that you could do this and still comply with building regulations.

At point of sale or letting you would by law be required to provide a BER Cert for the alterted house. So first call has to be to a BER assesor to advise the issue before you do any building work. Your BER Cert should help you track down the original Assessor.

The BER Assesor can advise on BER impact and on building regaulations impact.

sligoman2015

Thanks for all the help!

Could anyone recommend an individual or company in the dublin area that does attic conversions and would have experience with dealing with relocation of solar panels / relocation mechanical ventilation heat recovery units & associated ducting to roof as well- ie do a turn key job on a modern BER A rated house?

I contacted several attic conversion companies, but they appear to be one or two man bands (nothing wrong with that) who are used to dealing with conventional houses. The standard line is get the solar person to move the panels and get the MVHR person in to move the MVHR unit and then I'll do it... So that can involve 3 separate contractors, and if something goes wrong like a roof leak etc its not clear who is responsible......

Thanks in advance for your advice

Strolling Bones

sligoman2015 wrote: »

The standard line is get the solar person to move the panels and get the MVHR person in to move the MVHR unit and then I'll do it.

This "standard line" is the responsible approach !

In the context of small scale contractors this is all new stuff. I would much prefer they were all as responsible as this i.e. that they not go messing about with installations for which they have no training or expertise.

Or in other words beware the candidate who simply says "no problem" and proceeds to work away. Avoid those chancers.

sligoman2015

Thanks Strolling Bones. Just wondering if there is a company out there that could do all stages of the work

sligoman2015

Hello. I am in the process of purchasing a BER A2 rated house 134sq metres. I want to convert the attic but the solar PV panels take up a large part of the rear roof space in a 3x2 grid.I can't get planning to put the veluxes on the front aspect and the design of the front roof makes solar panel placement there difficult and unattractive. I may have to put in a smaller grid or leave out the solar panels altogether so as to accommodate the velux rooflights. Is there a minimum size / electricity generating requirement for solar PV panels relative to floor area as part of the renewables part L regulations and what is the effect on my BER of removing them altogether? Thanks in advance for any help.