Staking out the Basement

Saturday, our kids each had soccer games, one after the other.  Each of my boys won their games (3 to 2 and 5 to 3). By the time the games were over, it was mid afternoon, we dropped them off with their grandparents and headed out to survey the basement.  We were using a builders level that I rented, again.  We had to do the job again because all the previous stakes were dug up during the excavation.  Well, I should say most were dug up.  Sherri had run some extra stakes further out so that we could re-establish the location of the center of the house.  The excavators had been careful not to disturb those markers.

When we got there, it was kind of cool to be able to drive up our new driveway…  Its the little things ;^)

We started with the long line that Sherri had marked out before the excavation.  We tied some masons line between the stakes that she had placed 50ft on either side of the center (the excavation was about 60 ft across).  We tied a plumb bob to the mason’s line at the middle point and let it hang into the excavation.  The sand was also very soft and rough, so I spent some time flattening the area, especially around the hanging plumb, with my 10” tamper.  I then positioned my marked concrete paver (90lbs) centered under the plumb and lined its etched angles up with the mason’s string overhead.  Then we setup the builder’s transit over the paver (I finally have that setup process figured out after three rentals).  Again, I used the overhead string (and the lines etched on the paver) to orient the transit.  It took us about an hour of setup before we placed our first stake, but once we did, the rest went fairly straight forward.   Since most of the key points for this design are positioned radially from the center, we just needed the transit for the angles and a measuring tape for the distances.  This marked out the centers of the edges, then we offset these stakes by one foot (half the width of the footing) to get the true outer corners.  In one corner, we use some Pythagoras (3-4-5 triangle) to square things up.  We also put a lot of “extra” stakes in to make the curved shape clearer and topped it off by tying string along the perimeter of the footings.  We actually had brought surveyors paint, but it didn’t work well on the sand.  

The pit had not been excavated far enough and I had to do some manual digging along the way.  The soft sand was easy to dig (I did all the work barefoot and pretended I was at the beach) but as I dug, the sandy wall would cave in and give me more to dig.  I couldn’t throw the dirt out of the hole, so I tried tossing it “out of the way”.  But I didn’t put it “out of the way enough” and I had to dig some of the same dirt again when I got to the next stake.  Sherri thought that was funny.  There were a few areas that had so much sand I just gave up and stuck the stakes in about where they would be.  We called the excavator to come back and widen the excavation.  That was a bit disappointing because it meant we would need to delay the start of the footings.   Anyway, we got it all staked out by 9:20 PM (just before it got dark), but it was probably closer to 10:30 PM before we completed the long drive back and picked up our kids (an hour and a half later than planned), so we appreciate that my in-laws were merciful and hope they will still help us out next time ;^).

Hopefully the Excavator will go back and take care of the over-dig without disturbing these stakes or the centerstone marker (paver) too much and we can get to work on the footings.  I found out that my footings guy uses a “Total Station” builders transit.  It has a computer that does all the trig for you.  We will let him stake it out next time.  I just need to figure out how to transfer my drawings into the right format.