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
Top 30 Days Experts
Rank Leader Points*
1 LCD 2590
2 kstreett 240
3 Guest_9020487 110
4 Guest_9190926 105
5 GoldenKid 100
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 3/26/2017

How much to pressure wash and reapply sand on paver patio

Do you have the same question? Follow this Question


1 Answer

0
Votes

For a cheapo job - $0.75-1.00/SF range should cover most areas, more professional jobs would normally be in the $1-1.50/SF range. For pressure washing and resanding with compaction of the sand and then resealing (which seals the pavers and also "glues" the sand together to minimize washout) more commonly $1.50-2.50/SF and even more if a lot of weeds and moss and such need to be gouged out of the joints - both assuming at least 100SF or more of patio area in the job.


Actually, for normal cleaning (as opposed to removing heavy moss buildup or ground-in tree drippings or such) pressure washing is NOT recommended for sanded paver/brick patios because it washes the sand out of the joints too much - use of a specific paver or brick cleaner product with stiff contractor brooming as necessary, then hosing off with a garden hose with adjustable spray nozzle is the recommended solution, with makeup sanding and spraying to settle it in followup after the cleaning is what is generally recommended for normal maintenance cleaning.


There are two schools of thought on the resanding - one is to pressure wash the pavers/brick including gouging out the joints, then when totally dry resand with a thick layer of sand and compact it into place with a plate compactor - same as with new construction, then broom/hose/leaf blow off the excess, then seal. The other is to pressure wash diagonally and try to avoid washing the sand out of the joints and skip the plate compaction on the theory that the pavers/bricks are already locked in by either sand grains or block-to-block contact so just brooming in the sand does the job. Obviously, recompacting with a plate compactor is more expensive (and generally considered more professional and generates a substantial amount of "wasted" sand), and if the subbase was not properly done (expecially if rocks and cobbles were left in it at the surface, or if placed on bare soil) plate compaction can crack pavers and bricks which are high-centered on stones or if pavers are tilting because the subbase was not properly done. But does do a much better job of working the sand tightly into the joints and "locking" the joints in place, and in settling down any pavers which have lifted up or tilted a bit.


There are also two thoughts on the sanding application - some manufacuturers and masons recommend dry sanding (and both the pavers and the sand has to be TOTALLY dry to prevent clumping and bridging, which keeps it from running down into the joints) - the other, which I prefer, is wet sanding (assuming drainage is not an issue, like the water moving toward the foundation) so the sand is washed more fully down into the cracks to totally fill them - though this does require about a 3/16-1/4" joint to work without plate compaction. Doing this assumes that there is proper base under the pavers - if a proper crushed stone base was not used under the bedding sand and around the edge of the bedding sand at the perimeter, then with wet sanding (aka sand flooding) you can end up with erosion/settling of the soil and the pavers, so if not sure the original job was done right then wet "washing-in" is not recommended. Consumption of sand when wet-washed in is typically 25-100% greater than with dry - giving clear indication that it does a much better job of filling the gaps in the paver surface.


There also two approaches on the sand used - one is angular silica sand, which is the traditional product - like a #20 to #60 sandblasting sand. (And common rounded general purpose or sandbox or beach sand is NOT recommended - while it does penetrate the joints better, because it is not angular it does not lock kthe block together as well, and also washes out easier in narrow joints (makes little or no difference in wide joints). Ocean beach sand (other than illegal to take in most areas) can also cause salt staining and adjacent lawn kill.


Newer is "polymeric sand" which may or may not actually have a polymer in it but is still called that, but has a binder - portland cement, clay, latex adhesive, or a true polymeric adhesive which when wetted binds the sand and reduces washout are used by various vendors. I have no opinion on whether it is really worth it (costs about 30-100 times as much as regular sand cost) and there are contractors who do paners and brick all the time who swear by it and will use nothing else - others say it is a waste of time and conventional sand works fine. But with teh polymeric sand the pavers/brick and the sand have to be ABSOLUTELY dry when placed or it will clump up - the sand also has a short shelf life and has to be protected from moisture so the binder does not start setting up in the bag - should be stored and treated like scaked portland cement until used.


[On the cost - regular crushed silica sand is about 2.5¢/lb bought in bulk, about 10-15¢/lb bagged - sandblasting sand about 10-20¢/lb, polymeric sand runs generally from about 35¢/lb on up to as high as $1.67/lb (I look that one up on Amazon for kicks just to see what people charged on there) - but around $1/lb appeared at several home improvement and box store and Grainger price lists - so as much as 70 times as expensive for the bagged polymeric compared to bulk sand, or about 5-10 times as expensive compared to bagged silica sand - though granted you are only looking at about 1/2-1 lb/SF with narrow joints, but can really add up if you have the popular new ridiculously wide joints which I think are just a scam to reduce the block count on a job.]


Note on the "polymeric sand" - it and the pavers have to be totally dry during application so can't be applied for typically 1-3 dry days after paver washing or a rain (or lawn watering wetting it), but the sand needs to be lightly sprayed with water to soak it and set it - then has to totally dry before applying any sealer, so the entire process can drag on a week or even much more if it rains. And the sand cannot tolerate any substantial rain until it has set after being placed and wetted.


Also, it has to be thoroughly removed from the paver surface before wetting to prevent staining (which can also occur if it is overwetted and washes the binding agent out onto the pavers) so takes an expert touch. Also has commonly a strong tendency to bleed and stain red and bluestone pavers and many types of natural stone - and the staining is VERY tough to remove - commonly requires sandblasting to get it off without streaking the pavers like high-pressure pressure washing will.


Personally, I recommend against sealing agents with brick, because it promotes water retention which causes most bricks to soften, deteriorate and spall. Sealing on pavers can (if maintained and redone yearly or so) reduce effloresence - the white deposits that form on the surface, but is a maintenance hassle so unless the customer is going to have a full-time grounds maintenance staff or is a serious yard DIY'er, I recommend against it because after a year or two it will be ineffectual anyway so to me is a case of pouring your money down the drain. Obviously, if you are a serious patio washer or are subject to frequent heavy rains and do not feel like resanding with a broom periodically when the cracks show low sand or voids, then the sealer may have some merit for you.

Answered 7 months ago by LCD




Related Questions


Terms Of Use
|
Privacy Policy