Insulating under suspended concrete floor?

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Wheelbarrow01

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#231814 14-Mar-2018 16:04

So the situation is that from July 1 2019, all rental properties must have insulation in the ceiling and under floors "where practicable". Seems fairly straight forward so far.

I have a 1970's rental property which is in a 2 storey block of 10. My particular unit is on the first floor, but there is no unit underneath on the ground floor - the entire space under my unit is occupied by 3 parking spaces, and only one of these spaces belongs to my unit. Essentially my unit is suspended in mid-air and held up by concrete block walls on 3 sides, with the 4th side open to allow vehicles to park underneath.

The floor of my unit is made of cast concrete panels, and is obviously held up by the 3 concrete walls downstairs along with a chunky concrete beam where the opening is.

I am wondering how practicable it is for me to install underfloor insulation, and what type I could use. I obviously own the top side of my concrete floor. And presumably I also own the underside of my floor - the ceiling above my designated parking space. But one potential sticking point could be that I don't know who owns the underside of my floor where the other two parking spaces are. Technically the underside of my floor is the ceiling of those parking spaces, so it could be argued that the two neighbouring property owners actually own two thirds of the ceiling space below my unit, so it may not be practicable for me to install insulation in those two areas unless the other owners agree. There are electrical wires which don't belong to me running across that ceiling area which complicates things further - I most likely have no right to cover those cables up, but nor am I enthralled at the thought of having to pay to relocate those cables.

It's an interesting conundrum. Whilst I would like nothing better than to turn up there tomorrow and apply insulating spray foam to the whole ceiling of the carport area, I feel like that could potentially be considered trespassing, and of course there is the cabling issue to address first.

At this stage I don't know who the other owners are. It's a case of traipsing down to the council offices to find out their name and address for service, and then sending them letters I guess.

It's a long shot, but has anyone else found themselves in a similar situation?

wellygary

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#1976574 14-Mar-2018 16:11

https://www.tenancy.govt.nz/assets/Uploads/Insulation-requirements.pdf

Page 17

Where the habitable space of another unit is directly above or below a ceiling or floor, this area does not need to be insulated. Particularly in buildings with Bodies Corporate, owners of units will likely need to seek permission to alter the thermal envelope of the exterior of the building. Bodies Corporate might consider incorporating the installation of insulation into their long term maintenance plans, particularly if a building consent is required to install insulation.

Your unit is directly above the ceiling of the carpark (which you do not on) , it should be exempt...

cadman

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#1976633 14-Mar-2018 17:34

wellygary:

https://www.tenancy.govt.nz/assets/Uploads/Insulation-requirements.pdf

Page 17

Where the habitable space of another unit is directly above or below a ceiling or floor, this area does not need to be insulated. Particularly in buildings with Bodies Corporate, owners of units will likely need to seek permission to alter the thermal envelope of the exterior of the building. Bodies Corporate might consider incorporating the installation of insulation into their long term maintenance plans, particularly if a building consent is required to install insulation.

Your unit is directly above the ceiling of the carpark (which you do not on) , it should be exempt...

Carparks, even enclosed garages, aren't habitable spaces.

Edit: See Page 8

Fred99

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#1976754 14-Mar-2018 21:08

This is on page 17 as well:

Outbuildings & Garages
Uninhabited outbuildings such as sheds
and stand-alone garages are exempt
from the insulation requirements.
However, where a garage is located
directly beneath habitable spaces, the
underside of the floor between the
garage and the habitable space needs
to be insulated.

If that's going to be an issue, then the fallback position of "where practicable" and arguing "not" might be an out.

I agree about the comment that it's an "interesting conundrum". Hope the body corporate is easy to deal with.

Wheelbarrow01

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#1976929 15-Mar-2018 07:53

Fred99:

This is on page 17 as well:

Outbuildings & Garages
Uninhabited outbuildings such as sheds
and stand-alone garages are exempt
from the insulation requirements.
However, where a garage is located
directly beneath habitable spaces, the
underside of the floor between the
garage and the habitable space needs
to be insulated.

If that's going to be an issue, then the fallback position of "where practicable" and arguing "not" might be an out.

I agree about the comment that it's an "interesting conundrum". Hope the body corporate is easy to deal with.

Thanks for the replies everyone. It almost makes things quite clear. Unfortunately this is not a unit title property with a body corporate. It is a cross-lease title, so all 10 owners have an undivided share in the land that the building sits on, but we each have sole ownership/use of our unit (and exclusive carport space). The hard part will be in determining whether the entire ceiling of the carport area beneath my unit belongs to me. Personally I think this is unlikely. However, just on interpreting the legislation from the quotes above, I should be ok to proceed with insulation (even compelled to do so), however I would still have to ask permission from at least the two other parking space owners. The cross-lease document may also require me to gain permission from all 9 other unit owners as most cross-leases have a clause that states that any building work or alterations to the outside of the building require everybody's permission. Of course I could argue that the carport ceiling is technically within the building footprint so is therefore "not outside", but it's a grey area.

It could be time to ask my friendly lawyer. Or direct this specific scenario to MBIE for their thoughts.

Thanks everyone for your responses.

Fred99

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#1976986 15-Mar-2018 10:18

Perhaps not a bad idea - if you could find someone to oblige - would be to get an insulation expert installer to take a look and give advice. I can't imagine yours is the only case - maybe they've come across the same issues before. They might also be able to give a rough cost estimate and options for insulation - if it can be done. I think I'd possibly do that before seeing a lawyer, they might be expected to know the legal details (but possibly only after doing some $$$ searches on title etc - before committing themselves to giving advice), but the lawyer probably knows less of the technical details than you do, so the more information you've got at hand the better.
That would also be useful if you're talking to other owners - though you're probably volunteering yourself to be nominated as "project manager" - which could be for better or worse :-)

geoffwnz

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#1978734 16-Mar-2018 15:27

Seems a bit obvious, but have you tried either putting a note on the other two cars to see who owns them, or just gone door knocking and asking people? There's only 10 units, shouldn't take too long to find who the owners are.
Might be quicker/easier than dealing with the council more times than you have to.

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Aredwood

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#1978924 17-Mar-2018 01:19

Another way of phrasing the same question. If the owner of the car park beneath your unit wanted to attach something to the ceiling above the car park. (your floor) would they need permission from you and the other unit owners? Or would it be counted as an internal renovation from their point of view?

Have you checked the flats plan attached to the title to the whole property? It should say if the car parks are common area, or if they are exclusively owned by 1 of the unit owners.

Could you just install extra ceiling insulation, and leave the floor uninsulated, so the overall thermal performance is still the same as the min specified in the act. Unless your unit has underfloor heating, typical heat loss via floors is only around 10% of total heat loss. And would probably be a lot lower for your unit due to the thermal mass of the concrete.

Kickinbac

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#1986605 31-Mar-2018 23:09

I think you are looking for a product like this.

http://mammoth.co.nz/range/mammoth-carpark-panel
[url=http://mammoth.co.nz/range/mammoth-carpark-panel]

Ive seen it used in commercial buildings to insulate the floor between an underground carpark or outside and the concrete floor of an office space above.

Wheelbarrow01

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#1987447 3-Apr-2018 09:53

Kickinbac: I think you are looking for a product like this.

http://mammoth.co.nz/range/mammoth-carpark-panel
[url=http://mammoth.co.nz/range/mammoth-carpark-panel]

Ive seen it used in commercial buildings to insulate the floor between an underground carpark or outside and the concrete floor of an office space above.

Thanks for the tip. I'll definitely look into this :)