The man from the damp company pressed a metal probe against the bottom of our front-room wall, watched a row of red lights come on and said, "There it is." It was ten past ten on Friday 25 April, he had been in the house about four minutes, and he had not yet looked outside.
The RICS survey back in October had flagged high readings at the foot of that wall and rated it a 3, which is the "needs further investigation" rating. We had put it off while the weekends were full of woodchip and Artex. Then a damp-proofing company offered a free survey, and free sounded sensible for people who had already paid £560 for a report and £180 for an EICR.
The free survey
He stayed about ninety minutes. He had a clipboard, a probe with lights, a stick of chalk to mark the wall and a tablet for photos of the skirting. His verdict was rising damp, a failed damp-proof course and plaster full of salts. The quote arrived by email that afternoon: a chemical damp-proof course injected along the front wall, plaster hacked off to about a metre and replaced with salt-resistant render, £3,800, with a 30-year guarantee. It asked for a 10% deposit of £380 to hold a date, and the price was valid for seven days.
I stared at the spreadsheet that evening. Finding £3,800 meant draining the house fund, which had £400 in it by then, and raiding the emergency fund for the rest. I had the banking app open on the deposit when Matt, who had been reading the survey rather than the quote, said, "Can we get one more opinion first?" I'd like to say I thought of it myself.
The second opinion
The independent surveyor cost £250 and came on Friday 2 May, one of my home days. He started in the front garden, which the first man hadn't. Crouching at the wall with a tape measure, he found the damp-proof course, a thin dark line of slate in the brickwork that should sit well clear of the ground. Then he showed me that the path was higher than the slate, and the flower bed higher still, with soil banked up against the wall. The bottom of the wall had been rendered in cement and painted, so the render ran across the damp-proof course like a bridge. Water had a clear route from the ground into the brickwork above the barrier.
His advice for our house was to lower the ground about 150 mm along the front wall, cut the render back, and leave the wall to dry before anyone touched the plaster. He wanted fresh readings over the summer, not that week. Nothing needed injecting. I asked what we'd be spending and he looked at the path and said, "Gravel, mostly."
Why the first meter was so keen
Both men used meters, but they measured different things. The first man's probe reads electrical resistance. Salts in old plaster conduct electricity and soak up moisture from the air, so it lights up red on plaster that may not be very wet. The surveyor drilled small holes at three heights and tested the dust in a sealed bottle with a gauge, which gives a moisture percentage rather than a colour. The numbers were highest at the very bottom and fell away within about 30 cm. Rising damp, he said, tends to climb higher and leave a tide mark, and the genuine kind is rarer than most people are told. This looked like water getting in at the base.
I'm not saying the salesman was lying. I think he believes in his meter. I just wish I'd asked him how he knew it was rising damp rather than water getting past the damp-proof course, and I wish I'd walked him out of the front door before he got his clipboard out.
We have costed the fix at under £100: gravel, a bag of sharp sand and a few tools, with Kev's trailer for the spoil. We'll do it on the weekend of 31 May. The wall stays as it is until it has dried. To sum it up: £3,800 quoted, £250 for the answer, a weekend of digging, and four mugs of tea across the two visits, one of which the salesman had, since we are not monsters.
