Timing of exterior grading
LearningtoBuild2025
| Posted in Green Building Techniques on
Trying to decipher when exterior grading should be done- I read some are adamant it be done before framing and others after framing is complete.
What’s the rationale for the different timing?
What timing of grading is best for a conditioned crawl space with foam board insulation and vapor barrier being installed prior to the framing being done?
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Replies
You didn't explain your build or your lot.
But in general, do the land grading after the framing, and roofing and the windows and the siding and the gutters/water management system. These trades will all mess up your grading if you do it before.
Not that I ever have any space to grade anyway, but I do grading when I'm doing landscaping which is the last step.
Jamie
Thank you this is what we thought made the most sense for reasons you mentioned.
Initially doing a very small studio cabin build on a slight slope. Crawl space. Will need to eventually bring in a little extra fill dirt and backfill a bit on 1-2 sides.
Clay soil.
LtB,
The rough grading (anything that needs a machine) gets done right after the foundation is back-filled. All the services should be in. You don't want large excavators working around the house afterwards, and tasks that rely on staging on the outside need a fairly finished grade to work. Final finished grading occurs when any patios, sidewalks etc. are put in. It's basically the last exterior job.
My GC refused to backfill before the floor joists and subfloor was in place. The logic was that the basement walls were less likely to get cracked by the weight of the backfill and equipment with the floor in place.
I don’t think it slowed the progress in anyway.
Walta
Most of the engineers I work with typically note in their drawings that floor framing and subfloor should be in before backfilling. It happens *most* of the time; in the few cases I know of where the drawings were ignored, no major defects occurred.
This makes sense, but it should be done right after that.
In my build, they kept delaying the grading. The result was the subs had no idea that the finish grade was coming up (they had excavated so much on the high side) so the hose bibs, the electrical meter and a few other exterior items are weirdly low...they still work, but its kind of strange.