Cavity Wall Insulation - drilling - brick damage?

dampsquib

I'm getting my cavities insulated, but one friend told me what a mess the drilling had made to brickwork in a neighbour's house ie: corners chipped off numerous bricks when mortar drilled.
When I asked the "quote guy" about potential damage, he claimed it would be minimal (but then he would wouldn't he!). He did say that 3 drill sizes are available: 26mm, 22mm, & 19mm. No extra charge for using the 22, but 19 was going to be a hundreds extra. I guess they like using 26 as it makes the job quicker. He said he'd put me down as "customer requests 22mm used" but I guess I'm going to have to "remind" the workers on the day.
Is the house going to end up looking like a machine gun battle has taken place? How "invisible" was the job in your experience?

ormus

suppose it depends on how picky you are?
mine looks ok. certainly at first glance. if you look closely i suppose you could say its not perfect?
but thats more to do with the color match of the mortar.

Gizmosmum_2

It really depends on the size of your mortar bed. As I understand it the 19mm can only be used with polybead insulation - great product with fewer, smaller holes but make sure they put the adhesive in with the bead otherwise if you take a window out etc the whole lot will end up in your garden! Probably costing more because there's not many people installing it.

22mm can still take the corners off your brick if the mortar bed is narrower than normal but usually if the mortar colour is matched and finished off properly once a couple of months has gone by you probably won't notice it unless it's pointed out to you.

Just think about the smaller fuel bills and keep an eye on the installers when they do the job.:)

WestonDave

We had ours done 18 months ago (bonded poly beads) - no idea what size drill they used. Our walls are limestone faced blocks so very pale and similar in colour to the mortar.

Firstly the number of holes drilled per wall is relatively small so its not like its been machine gunned. There will probably be a couple under each window (as obviously it can't fill from above), and then maybe holes spaced at 4 feet at 2 or 3 levels. (Can't remember and not at home to look!).

You can see where they have drilled if you look, but certainly on our walls its not blindingly obvious - I would say its pretty subtle and will obviously weather in over time. I guess if you have red brick its going to be more obvious if they've nicked a corner of a brick than if you have bricks that are nearer to mortar colour.

27col

I got mine put in from the inside when I built the house, so nothing shows. Just as well as it turned out. Because the bricks are a decoratively faced engineering brick and are very brittle. They would have flaked badly, if the drilling had been done from the outside.

David_Aldred

Hi dampsquib,
Please consider checking the condition and type of the cavity wall ties before installing your cavity insulation in addition to ensuring there is no debris within the cavities / at the base of the cavity wall as to address the ties and such debris once the insulation has been installed can be very problematic including risk of increased dampness. Kindest regards, David Aldred Independent damp and timber surveyor