Damp patches on internal wall

Sebandliz

We own a 1900's end terrace house. The gable wall needs a little attention and we have received a quote of £630 to have part of the pointing renewed.
Today however two damp patches have developed (we have had heavy rain) about 1 1/2 to 2 meters up the wall on the interior but in two separate places. Stange that both patches developed on the same day but on different walls.
There is no leaking pipe and we think it must be penetrating damp. Could it be rising damp developing that high?
The builder we have asked to complete the pointing can't come for a few weeks. Is there anything we can do in the mean time to stop the damp getting worse?
I hope the pointing fixes this problem. If it doesn't I don't know what could be the cause.

DTDfanBoy

Whoever you had in to quote on the repointing, may have removed some of the existing mortar and not replaced it. Maybe have a look on the exterior wall above the damp patches to see if there are any obvious gaps.

Sebandliz

Thanks. Had a look and there are some gaps in the mortar. There is also pebble dashing along the bottom 1 1/2 meters of the gable wall which was done before we moved in. The damp patches are the same level as the end of pebble dashing. I think this could be a factor. Maybe the pebble dashing is hiding something.
We've been in the house for nearly 5 years so would have thought any problem would have shown by now.