Extra insulation, existing loft conversion

[PhilFromYorkshire]

Hi
I have an existing loft conversion built and signed off by building control in 1992. I am considering improving the insulation. The house is a rental property and I want to get it to an EPC C rating.

From what I can find of the standards at the time, the insulation should have a u value of 0.25 W/m2K (u value of 4 m2K/W). Over boarding the ceiling with either 62.5 or 72.5 mm kingspan backed plasterboard seems like it will get me to about the modern standard.

However, the head height at the top of the stairs is already a bit low. It's 1.73m at one side and 2.17 at the other.

Should I worry that the ceiling height will be reduced further?

Is there a registration a tradesperson would have to certify the work that would satisfy the EPC inspector?

 

[Deluks]

If you are overboarding anyway, why not rip out the existing plasterboard first?
Then you can inspect what's underneath and check that vcl is intact and that there's no rot.

 

[cdbe]

Your best bet would probably be to get a local inspector on board with your plans and ask him what you'd need to do to achieve a C, and what evidence he'd accept (before and after pictures?). You can put less in areas with limited space and compensate with more elsewhere. I suspect any kind of "certified installer" would want silly money for what is a simple job.

I presume you've already covered the easy nonsense (light bulbs, trv's etc).

 

[PhilFromYorkshire]

Thanks for the advice. You're right, probably best to speak to an inspector.

Yes, all the easy stuff is done. According to the last report it needs the loft conversion insulation bringing fully up to standard to get to C.

I think ripping down the existing ceiling is not going to happen. That's a lot of unnecessary time and mess.