The Brew Cabin

Posted: **Fri Aug 08, 2014 1:39 pm**

Hi everyone,

I have a two year old house with a first-floor patio (above a garage). I have no idea what's in-between the patio and the garage roof although I'd love to think it was concrete (probably not, probably timber).

You can see an image here...https://www.dropbox.com/s/4b75wlbkrg3862f/WP_20140804_15_08_28_Pro.jpg

White stains have recently started to appear on the patio but are heavily concentrated in in one place. To make things worse there is a high number of trees and the patio often has leaves sitting on it for days (they get wet, make a mess etc).

I've been on this site and I'm sure it's efflorescence. My questions are;

1) Is it efflorescence?

2) Is it coming up from below the patio or is it likely that the leaves are causing it

3) How do I clean it off, read here that brush and then clean soapy water

4) Could I seal the stones after cleaning to prevent, obviously depending upon the answer to #2

Many thanks for any help.

Lee.

Posted: **Fri Aug 08, 2014 5:44 pm**

lee
yes it is efflorescence

sweeping leaves off weekly is a simple job that helps

sorry you cant stop efflorescence

it goes after a while

are the falls good on the patio?

if it is laid on wood you will likely have major rot problems down the line

LLL

Posted: **Fri Aug 08, 2014 11:12 pm**

Looked at the photo, what are this tile/pavers?
Your problem is the pointing/grouting?
Might be efflo might not.

It's not the leafs causing this, if it's only a 2 year old house, go back to the builders and find out what was used in the construction.
With that info might be able to help you.

Posted: **Sun Aug 10, 2014 10:52 am**

Many thanks for the responses,

The "fall", if this is how well the patio drains then it's marginal. The smallest amount of leaves around the drain area (2 holes in the wall) cause water to pool (you can see one of these drain holes in the pictures below).

Basically, I'm now wondering if it's simply water penetrating the grouting (not sure if this is the correct term) as water pools, this water is trapped as I'm guessing there's a waterproof membrane (this is above a garage), and then it makes its way back to the surface over time.

I've attached some more images that may put this more in context, the efflorescence is more pronounced closer to the outside wall of the patio where it drains to (I guess this is where it "falls" to). However, most of the patio area is starting to show signs now.

I don't know what the tiles are but they were from B&Q (spares I have still have barcode on) and they look like slate. These are all around the house but this problem only manifests itself on this first floor patio, everywhere else like the day they were laid.

I'm delaying contacting the builder until I have more information. It worries me as to what the real remedy to this problem will be.

Image showing drain and fall

Image showing effect are worse closer to fall

Many thanks again,

Lee.

Posted: **Sun Aug 10, 2014 11:34 am**

hmm if its slate it must be coming from the grouting or the bedding
did he use flexible external adhesive?

did he use ditra mat?

cheers LLL

The Brew Cabin

Efflorescence and any remedy