Dry rot & spot & dab

iamlucky18

We bought our first ever house in March. Not getting a full in depth survey done was probably the biggest mistake we have ever made (& costly).

The previous owner blocked off all the air bricks, creating the right conditions for the rot to grow. I've got a specialist company (peter Cox) to come in and do the treatment, but they asked us to remove tiles, pipes etc. out of the way.

The plumbers knocked off the tiles of the downstairs bathroom, and the dry rot has grown behind the plasterboard. One of the plumbers commented that the plasterboard was put on using a spot & dab method, and the lack of ventilation created the right conditions for the rot to grow behind it. It also seems this is the "sink" of the problem, as most of the growth is underneath the bathroom floor (which collapsed in whilst the plumbers were working - thank god nobody got hurt).

Do the air bricks also help to ventilate the the air gap behind the plasterboard too?

How should plasterboard be applied to brickwork?

The plaster itself is really thick in other parts of the house (at least 15mm). This isn't normal, is it?

I'm just a bit weary that Peter Cox might not do the replastering the right way (may be I'm worrying too much?).

Cheers.

new_owner

Dot and dab is fine under the correct circumstances. By the sounds of it I dont think it would have mattered to much how the plasterboard was attached to the wall. Even a framework with plasterboard attached would have had the same problem.. if not worse.

15mm is not that unusual in older houses.

You mention "sink" and bathroom. are you sure this is dry rot or wet?

The air bricks will ventilate under the floor (assume you have suspended floor) if plaster board cavity is attached to this then yes... however you might end up with a cold house if this is the case. easy to solve but will require a bit of work.

You could remove the dot and dab and replace with battons. insulate between and plasterboard over the top. you do loose some room. Or you can friction fit solid insulation and plasterboard with insulated pins. This is what I have done in some rooms. (depends on services behind and what you are attaching to the wall.

cyclonebri1

Yes, nothing at all wrong with that plastering method, almost all modern homes are done that way.

Read up on both wet and dry rot, they are very similar in some respects