Beaded cavity wall insulation

podge3

My house is about 10 years old and I'm thinking of getting the pumped beaded insulation. I have a few queries:

• Will it be effective in my house? Its a standard double leaf wall with polystryene board, so I understand the remaining 50mm gap will be filled.
• I am concerned about water penetration once the 50mm gap is filled. One reason for the gap is to prevent water ingress from the outer leaf. Is there any chance that water can get across the beads once the cavity is filled?
• My attic is floored. Is there some way I can replace the floor afterwards?
• Any pointers about the job itself? I believe the mains cable in the cavity should be protected. My alarm cables are also in the cavity. Will these be affected by the beads?
• I got a flyer in the door quoting a price of €1250 (€600 after the grant) for a 3 bed semi. This includes the cavity insulation and also the attic. Is this a good price?

sydthebeat

podge3 wrote: »

• Will it be effective in my house? Its a standard double leaf wall with polystryene board, so I understand the remaining 50mm gap will be filled.

yes it will be effective, you will be doubling the insulation in your cavity.
any cavity under 50mm will not be filled, so ensure theres a minimum of 50mm.
we got our office pumped on wednesday, the difference was noticeable within 24 hours.

podge3 wrote: »

• I am concerned about water penetration once the 50mm gap is filled. One reason for the gap is to prevent water ingress from the outer leaf. Is there any chance that water can get across the beads once the cavity is filled?

thats a valid concern, but these systems are certified to say that moisture does not penetrate to the inner leaf. There is a glue substance thats pumped in with the beads which effectively makes it waterproof

podge3 wrote: »

• My attic is floored. Is there some way I can replace the floor afterwards?

what has that got to do with pumping the cavity?

if you are referring to getting the attic insulation increased, then really you should:
1. take up the flooring, and store for reuse
2. (assuming you already have insulation between your existing joists)
lay joists perpendicular to the existing, which are high enough to ensure a min of 300mm insulation in your attic. Probably 150s or 175's will be needed.
2. get your insulation installer to lay the new insulation between these new joists
3. refloor attic with reused flooring. ensure to drill vent holes in attic floor every 600mm centres to allow for venting over insulation

podge3 wrote: »

• Any pointers about the job itself? I believe the mains cable in the cavity should be protected. My alarm cables are also in the cavity. Will these be affected by the beads?

if applying for the grant, theres an in-depth specification of works included under the HES scheme, have a look.

podge3 wrote: »

• I got a flyer in the door quoting a price of €1250 (€600 after the grant) for a 3 bed semi. This includes the cavity insulation and also the attic. Is this a good price?

sounds definitely on the high side. an average quote around here would be €1000-€1100 for a 3 bed semi, 50mm pumped and 200mm attic insulation installed.

whatever you choose to do, get at least 3 quotes... in todays climate there will be no problem getting guys to quote for you.
and remember, only SEAI register installers can be used in you want to claim grant.

podge3

Thanks for the very detailed reply, Sydthebeat.

And yes, my attic question was referring to getting the attic insulated.