Archive for January 6th, 2009

Trenching for the Foundation Drains

Tuesday, January 6th, 2009

It was a cool dry day today – perfect for trenching the perimeter drains under the foundation.

The tarps were pulled back in the morning and the two machines on site cleaned up the ramp going to the excavation.

Starting perimeter drains for foundation.

Starting perimeter drains for foundation.

After Jorge established the drain locations, they started digging the trenches. One truckload of dirt was removed as the void will be replaced with pipe and 3/4 inch crushed rock (over fabric).

Trench for perimeter drains under foundation.

Trench for perimeter drains under foundation.

All of the perimeter drains will lead to the sump pit. With the tarps pulled back, the 36 inch wide vertical sump pit in the south-east corner of the property was exposed, in all its glory. We’re loving the sump pit!

Sump pit in south-east corner of property.

Sump pit (36 inch vertical culvert) in south-east corner of property.

Why?

On our property, we have a ‘seasonal perched water table,’ which creates a number of costly issues. First, we have to deal with almost 500 lbs per sq ft of hydrostatic pressure, which is why our house must weigh at least 1.5 million lbs. Second, the water encountered caused the drilling and pouring of our shoring piers to take longer than expected (and cost much, much more than anticipated). Finally, the water requires waterproofing of the foundation and sump pumps in several areas, which is causing design delays and controversy and, go figure, lengthening the construction timeline and corresponding costs.

So, anything that reduces the level of the seasonal perched water table reduces the hydrostatic pressures on the foundation and, in turn, reduces the risk of water entering our house. We don’t want any water inside the house.

Yeah, we can’t wait to ‘show off’ our beautiful new dual electric sump pumps, complete with independent back-up natural gas generator. Oh, did you see that the stairwell and window wells have large capacity 3 inch drains going to the sump pit? And, if those get blocked, there are 2 inch overflow drains going to the sump pit. Very cool … not.

Although I didn’t meet with Bill Brown today, we did sort out the drains from the stairwell and window well, and how that ties into the sump pit.

A bright spot in the day was the surprise visit by Sandra Ayllon, an estimator for Bill Brown Construction Company. She had a meeting only a block away so, being friendly, she stopped by our job site to monitor the progress and say hi to everyone.

Sandra monitoring progress at the end of the day.

Sandra monitoring progress at the end of the day.

Bill has a competent, dedicated team that work together extremely well. It is fun to work with his team.