Ask Your Question

Angie's List Answers is the trusted spot to ask home improvement and health questions and get answers from service companies, health providers and consumers. For ratings and reviews on companies in your area, search Angie's List.

 
 
or
Submit
Top 30 Days Experts
Rank Leader Points*
1 kstreett 240
2 Guest_9020487 110
3 Guest_9190926 105
4 GoldenKid 100
5 mygfcxx1 95
6 ahowell 95
7 KnowledgeBase 95
8 skbloom 80
9 Guest_98024861 70
10 Guest_9311297 70

*Updates every 4 hours

Browse Projects By Category

Question DetailsAsked on 1/6/2016

How do we permanently stop the brick and/or mortar on the floor of the front porch from "leaching" white residue?

Brick/mortar is approximately 2 1/2 years old and problem did not start until 3 months ago. Area catches the afternoon sun and residue appears to occur where direct sunlight has hit. Have used plain water; soap and water; white vinegar (both diluted and un-diluted) which has stopped the residue for a short time but it again re-occurs.

Do you have the same question? Follow this Question


2 Answers

0
Votes

What was originally done that it lasted 2 yrs 3 months before the problem presented itself? I know the builder who did our house washed the bricks with some solution but dont know what it was.Two years at a time is way better results than what you've had recently. Seems like an odd problem to have but then I am pretty much an indoor person. It could be happening here at my house and I just am not aware of it. Good luck finding a lasting fix to the issue!!! Peggy

Answered 3 years ago by PMiller

0
Votes

Unless you have very poor quality bricks, what you are seeing is lime water leaching out of the mortar - and this will occur whenever it has gotten wet then dried out, because as the lime water evaporates at the surface it leaves a lime coating, which when it dries is basically a thin limestone layer.


White vinegar or spray Lime Away can remove it (use in moderation without soaking the mortar, as it eats mortar too) - heavier buildups require sponging with muriatic acid (dilute hydrochloric acid, which is probably what the other commenter was talking about) to remove it - it is also used for initial cleanup of lime and cement on the brick surface after construction.


Stopping it - general sealing of brick is not recommended, because water gets in through sealcoats through scratches and pinholes (especially in walked-on surfaces) but cannot evaporate back out the same small openigns, so the brick stays saturated and the mortar and bricks (if not fully-fired firebox or porcelain bricks, which they VERY rarely are in house construction) gradually soften and break up.


One thing that can be done - differences of opinion on this, but has worked for me both in outdoor environments like yours and on floors that get frequently wet-mopped or frequently get and stay wet (like entries and mud rooms) or are wet-cleaned by machine, is using a tile grout sealer hand-brushed ONLY onto the mortar joints, leaving the bricks uncoated to allow evaporation. Will still form a limited amount of laittance (the lime buildup) but can reduce it dramatically.


Another thing sometimes done for this is grinding or gouging out the top 1/8-1/4" or so of the mortar and replacing with exterior/floor sanded latex modified tile grout, which wears better, is more water resistant, and does not leach out lime anywhere near as much. This is a common fix for deteriorated brick floor mortar joints, but does look different than normal mortar if done as a spot fix.


One possibility here - is that normal house bricks and mortar were used (as they commonly are), instead of "lay" or "floor" bricks and latex modified cement mortar. These are a much stronger brick and a harder mortar (more like tile mortar) that do not soften and leach out nearly as much. Of course, too late to change that if that is the case.

Answered 3 years ago by LCD




Related Questions


Terms Of Use
|
Privacy Policy