ALERT!!: If you build segmented RETAINING walls
there is something you should know, you may be at risk. With ease we could make this a 4 page article, instead it will be divided
among other future blogs under different headings. Based on a serious
scenario that played out a few seasons back and due to the sensitivity it captured the attention of some industry leaders.
What we think we know, what we know, and what is preached about wall construction via block
manufacturers as good business practice and industry standards, as
advocated by NCMA will come into question. This may present a whirlwind of
confusion. As Individual contractors in the Hardscape construction
industry you can decide what will be in your own best interest. So here
we are..... As a general rule of thumb we all have heard through out the
industry that GeoGrid is required behind a wall at a finished height of 4' and above. This has been
interpreted by contractors as "we never have to use GeoGrid unless the
RETAINING wall is 4' or above". The rule of thumb is incorrect as well
as the interpretation.
Here is where it begins....GeoGrid can, may
and should be used on RETAINING walls less than 4'. This is not my
"Alternative Perspective". It is how ever a circle of confusion that begins
with the block manufacturers spec. Now I'm not pointing blame, this is not a
blame game. However the awareness of many contractors not knowing or
misinterpreting this grey area will begin to unfold as
industry professionals begin to participate in this blog. If you enjoy
this blog you will want to read the "Wally.... Nope, Folly!" Future
blog. Thank you for reading. This is my Alternative Perspective.....
What is yours?
To geo-grid or not to geo-grid??? A contractor should base his decision to use geo-grid on the manufactures recommended wall heights(before engineering is required), local building codes, site conditions, soil conditions, slope behind the wall and the actual type/style of wall block they are using. Using geo-grid is cheap insurance against a failure when installed properly.
ReplyDeleteA few good points... Most block manufacturers have a product spec guide or something equivalent. once the product selection is made check the "recommendations" to determine if the block is suited for the application in question and geo-grid parameters. That's a good 1st step prior to to contacting the local building inspector.
DeleteNice opener. The manufacturer product specification guide is a tool. One that is under utilized. Build to the manufacturers designed spec and you shouldn't have an issue. If by chance you should have an issue and can validate you built to the recommendations, then in theory it's now back on the manufacturer. Back to wall spec., I am surprised no one has mentioned this yet. Your article tells the reader to view the spec, I wonder how many guys out there don't know that the majority of the segmented retaining walls being installed have a recommend spec for the introduction of grid at an average height of 30". If that's the case folks, than what is being implied????
ReplyDeleteWhat does it imply??.... What does it imply? Great question! Installers think about how I present this and give it some thought. If the manufacturer recommends that at the height of 30" you should integrate Geo-Grid in your wall, then ponder this. Here are some suggested "good business practices" Put project name on all your invoices pertaining to the project. If you intend on having multi slips with wall stone on them be sure to have Geo-grid on the initial wall order. If there is no grid on any of your invoice for the project and you unfortunately should have some type of failure you will find it very difficult to summon any support of the manufacturer of the installed wall block. If the issue results in a legal issue then the manufacturer may technically not be obligated due to your failure to build to the manufacturers recommendations. Contractors that are reading this, Our mission of The Hardscape Rant blog is for you all to interact to ensure quality topics and further education in your industry.
ReplyDelete