How can I seal Sandblasted interior brick?

[TSS]

I’ve had the interior of a Victorian outbuilding I’m converting to a garage sandblasted to remove layers of old paint. The bricks and mortar now look really good but I am concerned that they may drop dust over time.

Can anybody recommend a clear sealant for them? Something that is breathable is essential because they had previously been painted with non breathable paint in some areas and that was causing problems.

Thanks,

TSS

[benmc]

TSS

I have been looking at this. Not tried it yet

http://www.decoratingdirect.co.uk/viewprod/h/HUMPS...

Ben

[B17NNS]

Thompson waterseal?

[eps]

I'd apply a sealant (such as Repelicone L) to the exterior, not interior!! With care though, if it's Victorian it's at least 100 years old, so it's not doing too badly. Then apply paint as before, inside.

Is there a DPC?

I guess it's double brick bonded without a cavity..

What provision have you got for rainwater removal and guttering? This is normally the source of most damp and water ingress problems.. Other items such as concrete paths surrounding the building also won't help as rainwater will fall and simply have nowhere to go apart from onto the brickwork at ground level...

[TSS]

benmc said:

TSS

I have been looking at this. Not tried it yet

http://www.decoratingdirect.co.uk/viewprod/h/HUMPS...

Ben

Thanks I'll look into that. I'm not sure if that one is breathable though, I may have to speak to the manufacturer. Can anybody recommend one which is definitely breathable?

eps said:

I'd apply a sealant (such as Repelicone L) to the exterior, not interior!! With care though, if it's Victorian it's at least 100 years old, so it's not doing too badly. Then apply paint as before, inside.

Is there a DPC?

I guess it's double brick bonded without a cavity..

What provision have you got for rainwater removal and guttering? This is normally the source of most damp and water ingress problems.. Other items such as concrete paths surrounding the building also won't help as rainwater will fall and simply have nowhere to go apart from onto the brickwork at ground level...

Thanks eps. There isn't a DPC and you are correct, it is double brick bonded without a cavity. I have recently fixed the guttering which was defnitely causing part of the damp problem as water was running down the exterior walls. But there is a brick path around some of it which probably doesn't help.

[eps]

A brick path may be okay, as the water can dissipate through the gaps between the bricks. Is there a French drain or similar between the wall and path?

I would be tempted to ensure that the roof and guttering and rainwater removal is working properly before coating the inside or outside.. Of course it's "summer" now so it should dry out anyway, but if you have a downpour, either look at it and see if there's water falling from odd places or go out and have a look and a listen.. Ideally rainwater needs to go to a soakaway, a minimum of 5 metres from foundations.. (current building regs)


As I said it's been there for 100+ years.. It just needs to be kept in good order..

[mas99]

I would be thinking about a dilute coat of limewash.

But either make your own or buy from a decent supplier (not F&B). Put a little linseed oil or casein in to help stop it rubbing off.

[eps]

TSS said:

Can anybody recommend one which is definitely breathable?

Repelicone S (it might have replaced L).. Breathable.

Tech sheet here : http://www.donconstruction.co.in/images/Data%20She...

Obviously if you get the above product ensure in a small spot that it doesn't discolour or react before applying all over!!

[TSS]

eps said:

A brick path may be okay, as the water can dissipate through the gaps between the bricks. Is there a French drain or similar between the wall and path?

I would be tempted to ensure that the roof and guttering and rainwater removal is working properly before coating the inside or outside.. Of course it's "summer" now so it should dry out anyway, but if you have a downpour, either look at it and see if there's water falling from odd places or go out and have a look and a listen.. Ideally rainwater needs to go to a soakaway, a minimum of 5 metres from foundations.. (current building regs)

There's no french drain but there are a few drains at stretegic places for water to run into. I will double check the guttering next time it rains - most days at the moment! The water all goes into a very efficiant Victorian drains system so no problems with soakaways.

eps said:

Repelicone S (it might have replaced L).. Breathable.

Tech sheet here : http://www.donconstruction.co.in/images/Data%20She...

Obviously if you get the above product ensure in a small spot that it doesn't discolour or react before applying all over!!

Thanks I'll look into that.

[mas99]

A silicon based product may describe itself as breathable but imo it certainly isnt breathable in the context of old buildings/lime mortar etc.

[eps]

mas99 said:

A silicon based product may describe itself as breathable but imo it certainly isnt breathable in the context of old buildings/lime mortar etc.

I don't know chap, I'm just quoting the manufacturers literature...

The rainwater shouldn't go to the drains, it should go to a soakaway.. but that would only need to change if you did building work and BC became involved...

[mas99]

Fair enough.

As a fan of using lime and having breathing structures I tend to get annoyed by many of the claims of 'breathable' that I see. In the rare event that they actually quote figures it generally turns out that it is anything but. If they require the structure to be dry before applying it then to my mind it isn't breathable enough.

But I do knit my own yoghurt....