<p>There can be different causes of damp patches still coming though after this has been treated with stain block. We need to carry otu further investigation to found if it is not a pipe leak or if the concrete slab is not wet, the damp patch is coming from the external wall of the cleaner&#39;s cupboard, in line with the concrete floor. Inside the cupboard we found some signs of previous leaks but none of the pipe was leaking, in one of the riser where the drain pipe coming through the concrete. The concrete slab was wet but is 2m away from the place where the damp patch appears on the stairwell. We recommend to hack off the plaster to check if the concrete wall is wet. Also recommend a moisture meter reading before starting the dehumidifier and on after 12 or 24 hours to check the improvement, to estimate when the repair can be done.&nbsp;</p><ul><li>Operatives to apply protective sheeting to work routes and working areas.</li><li>To check the smoke isolation is in place or protect the smoke detector.</li><li>To remove the existing plaster to at least 300mm clear of all signs of damp or salt and at least 1 metre above ground floor level (approx 1m x 4m).</li><li>Check&nbsp;the concrete to see if it is dry,&nbsp;if it is wet we will need to install a pump dehumidifier.&nbsp;</li><li>To install the pump dehumidifier and connect the hose direct to a sink.</li><li>After the concrete has dried, brush the walls to remove all plaster residue.&nbsp;</li><li>Wet the walls and apply 2 coats of salt neutralizer, wetting again with fresh water between coats.&nbsp;</li><li>Apply a thin coat of render.</li><li>Apply a second coat to the same specification.&nbsp;</li><li>Whilst still damp apply a skim coat of multi finish.&nbsp;</li><li>Delay any decoration for at least a month, leave the dehumidifiers for at least 3 weeks.&nbsp;</li><li>After a month to paint the walls with 2 coats of matt white.&nbsp;</li><li>Site to be left clean and tidy.</li></ul><p>The works consists of in and out of hours work.&nbsp;</p><p>Our total cost to carry out the above works&nbsp;in normal working hours shall be &pound;4,165.00</p><p>Breakdown:</p><p>Labour: &pound;3,000.00</p><p>Materials: &pound;415.00</p><p>Plant &amp; Machinery: &pound;750.00</p>