External wall insulation in a damp house

After the insulation is installed you Will se the results in first 2 weeks the damps will start to disappear.

it will make it worse . your house was built to breathe by insulating it it will have the opposite effect, moisture trapped in the brickwork will create cold damp walls this will attract condensation creating further damp. Read the heritage property web site to better understand how your property was constructed & how the materials used in its construction all worked together to keep it dry, new materials and old houses don't work as they are trying to achieve different things,

Yes I agree adding insulation to the exterior of your house will attract more moisture as your home is built with a breathable membrane between the walls and this would not do its job if you are to block it

Moisture in the air condensates when it touches a cold surface, so insulating your walls should help to balance the temperature. You might want to research installing a PIV in your loft to maintain airflow throughout the property.