HELP - CRUMBLY MORTOR JOINTS IN BRICKWORK

[fazmann]

We moved into our new house in october 2008... since then we added a new central heating system, replastered, new electrics etc... it was a relatively negelected property, built in 1890. We opened up a chimey breast that was blocked in the kitchen. Since then we have been getting some white efflorence on the bricks and the mortar is crumbly... we added some window vents in the area..and efflorence seems to have pretty much stopped.. this posed be however to start looking around the property at the brickwork..i went into the loft areas...and pretty much all the mortar in the bricks is like sand in parts, and you can literally wipe the mortar out with your fingers?? i am now panicking that the building will fall down or something.... is this relativley normal for an old property... its rendered on the outside...and the render seems pretty solid? what should i do... i ahvent money to start get things like render taken off, and new things put back on? is there any thing I can do..or should it be o.k.. the surveyor when we brought it did not mention anything about crumbly mortar in places?

 

[stuart45]

The mortar will be lime mortar on a house of this age, which will be softer than cement mortar. I wouldn't take the render off if its in good condition.

 

[fazmann]

would you say just leave it alone then and it quite normal, or when the joints are particlary crumbly should I try and repoint with standard mortar in small sections (from the inside of the loft area) ?

 

[stuart45]

Its quite normal for old lime mortar to be a bit weak, but if you are really worried you could re-point it. As it's in the loft you could bag rub it, which is quicker than using a pointing trowel.

 

[fazmann]

thanks for your reply... im a real novice, so what is bag rubbing?

 

[fazmann]

and last question, would i have to use a lime mortar, or can i just use a ready mixed mortar?

 

[wavetrain]

thanks for your reply... im a real novice, so what is bag rubbing?

http://www.google.co.uk/search?hl=en&q=bag+rubbing&btnG=Google+Search&meta=&aq=f&oq=

 

[stuart45]

To bag rug your wall you need to rake out the joints firstly, brush out the dust and then damp them down. Then on site most bricklayers used an old wall tie sack, but an old sponge will do. You can rub the mortar into the joints a bit like grouting tiles. It won't look very pretty but it fills up the joints quickly. After they are filled brush of the excess. Ordinary mortar will do inside.