fixing damp with an industrial heater?

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The side wall of our semi detached 1930s house is made from a double thickness solid wall on ground floor and a single thickness solid wall above that. This wall, predominantly the ground floor, but also some further up, was diagnosed with damp at the beginning of winter. It has been damp for a couple of years as when we bought the house in 2018, damp came up on the survey.

The surveyor who looked at it in December last year identified various issues causing the damp, predominantly 1930s pebbledash not being great for walls, the pebbledash itself having lots of cracks, the DPC being too close to the external ground layer, inadequate drainage, various cracked downpipes. We have taken off all the pebbledash, dug a trench to install an aco drain and are planning to improve the wall by affixing 40mm K5 insulation externally and then rendering over that. All drain pipes will be replaced as well.

 

The insulation will stop the breathability of the wall on the outside, but to mitigate that we are using a fully breathable build up internally, with a ventilation gap. The surveyor is happy that this will be a good solution but would like us to dry the wall a bit more before doing this. His "belt and braces" solution for drying it was to install a temporary render on the outside (instead of the K5) that will draw out the moisture and then take it off after a couple of months and then do the K5 and finished render. This is quite expensive as it effectively triples the labour as well as adding material cost.

 

As an alternative, he suggested we hire some large dehumidifiers and run them for a couple of weeks. The difficulty we have is that we are not air and water tight yet, so I don't think the dehumidifiers will work well until we are. Most of the windows are in, but they've not been sealed yet and there is a large 4.3m by 2.1m gaping hole at the back of the house where we are still waiting for the sliding doors from Sunflex. 

 

The wall is on the side of the house in an alley way so doesn't get much/any sunlight, particular at ground floor where the damp is worse.

 

My builder has a large space heater, a bit like an industrial sized hair dryer and I was just wondering if it would make any difference if we blasted the wall with that for a few hours a day for a week? It would surely heat up the bricks and allow the moisture to evaporate, but could it damage the bricks in any way?