Jet washing roof tiles on house

nobulljusttruth

1321 ..........


that is how many roofs I cleaned personally with a jet wash for a local council. (Well not me exactly, ;the men,)

3 estates, with moss, and then fitted copper strips to the ridge.
We got £300 per roof and we did the whole thing off scaffold.

2786 sq mtrs: a hospital roof we cleaned, with a power washer ( well 4 washers).

Why

Because concrete is a good souce of lime, Moss roots get in, tile life is reduced. The weight added to a roof when it rains is double the volume of the moss soaking up the rain. (6 skip loads off the hospital).

Marley etc etc do not want people to restore roof tiles, they want them to replace them.

Copper strips create a copper sulphate solution when rained on (less now a days since acid rain is no longer a period).
Not enough to remove moss, but enough to discourage regrowth.

Do not listen to those with opinions that have no basis.

Loacl council saved £13 million in new roofs, for a few year longer.
(Apparently)
:beer:

Cakey87

Has anyone heard of a company call Cosey Homes? they have offered to Jt wash the roof, replace and broken tiles and then coat it with some water proof paint... the sales guy gave us a very nice presentation (we dipped our finger in some solution and put it in water and when we took our finger out it was bone dry) we signed up for them to start work, have i made a big mistake? it cost me 5k ??

wallbash

Do not listen to those with opinions that have no basis.

Just listen to a poster with a financial incentive.
Should we pushing the SPAM button?

ey143

He makes a valid point - why should it be spam just because you don't agree with it.

Doozergirl

I've never heard anything as ridiculous as waterproofing roof tiles - tiles and bricks are frost proof already - that's why they're used to do a job.

What makes me uncomfortable about jet washing is subjectin the tiles to something they aren't designed for. Roof tiles don't form a sealed barrier against rain, they are laid relatively tightly against each other with no fixing compound to seal the gaps anywhere. It's the angle they are laid at that does most of the job and the roof felt underneath. They're relatively delicate. Be prepared to set about repointing ridge tiles afterwards on a period house. The power of jet washing is going to dislodge anything that might be remotely loose. You may end up doing more harm than good.

If dirty tiles make the house look unrenovated, then I'm not sure cleaning them will improve it that much. Washing isn't renovating. Replacement with a different tile and some shiny new breathable membrane might be better.

How did you get on with the structural engineering aspect of your extension? Did you see the house that collapsed in Birmingham? We've worked on two house on that road so I was very interested to see it. Having looked at the planning application, they were removing a lot (too many imo) internal walls for a renovation. I blogged about it with the ground floor planning drawings. It's really important to get the right people on a job like that/yours.

wallbash

ey143 wrote: »

He makes a valid point - why should it be spam just because you don't agree with it.

You may agree, I don't.

ey143

Doozergirl,

Hi - was travelling so only now catching up with msgs. Yes, I did see that in the news and read about it, and immediately msged my possible builder about that as that did worry me. I will reply to the original thread.

Can you pls PM me the link to the planning history for that house, I'm curious to see it myself.

Thanks.

nobulljusttruth

wallbash wrote: »

Just listen to a poster with a financial incentive.
Should we pushing the SPAM button?

I have no financial incentive I am retired. My company was one of the few with a positive mention in the good old 'Aquashield' thread here on MSX.
I think that ran to 112 pages a few years ago.

There is NOTHING wrong with power washing tiles they are just concrete. like paving flags but higher up. The sealant used are OK, its the cowboys selling and applying the product that give it a bad name. I will not go into this now, but
I once filled a 3mtr skip to over flowing off a 176 sq mtr bungalow. I asked the skip company to weigh the contents before dumping, and the moss weighed 4.454 TONS.
The weight alone is enough to get it off and simply scraping is is like cutting the lawn.

Thats the last post on this subject from me.

nobulljusttruth

Cakey87 wrote: »

Has anyone heard of a company call Cosey Homes? they have offered to Jt wash the roof, replace and broken tiles and then coat it with some water proof paint... the sales guy gave us a very nice presentation (we dipped our finger in some solution and put it in water and when we took our finger out it was bone dry) we signed up for them to start work, have i made a big mistake? it cost me 5k ??

YES it should cost no more that £20 sq mtr. for clean. repair and coat. If they really do 2 coats, it has to be done over two days. If they do not use the undercoat, or coat over wet pointing in the ridges or valleys this is also wrong.

sorry

tony6403

nobulljusttruth wrote: »

I have no financial incentive I am retired. My company was one of the few with a positive mention in the good old 'Aquashield' thread here on MSX.
I think that ran to 112 pages a few years ago.

There is NOTHING wrong with power washing tiles they are just concrete. like paving flags but higher up. The sealant used are OK, its the cowboys selling and applying the product that give it a bad name. I will not go into this now, but
I once filled a 3mtr skip to over flowing off a 176 sq mtr bungalow. I asked the skip company to weigh the contents before dumping, and the moss weighed 4.454 TONS.
The weight alone is enough to get it off and simply scraping is is like cutting the lawn.

Thats the last post on this subject from me.

And 3 minutes later you did another one.
Did it occur to you that the vast bulk of the weight would be that of the water that you power washed into the moss?
Power washing a roof is bonkers ; walking on a roof to do this is likely to cause unnecessary damage to the tiles.
It would be interesting to know how insurance companies would react to any claims (over the long term) for water penetration if they knew that power washing had been done.