Deck pier undermining: multiple concerns

My first concern was that steps needed to be taken to prevent further undermining of the support piers. They seemed to have enough bearing to support a vertical load as long as no more erosion took place.
Then I realized that in their current condition they no longer resist a lateral load and the only resistance to a lateral load is the deck connection to the home and to a fire pit built into the deck (#5). The framing included no lateral bracing. At that point I changed the recommendation from correction by a qualified contractor to evaluation by a structural engineer.
It felt solid with just a few of us on it, but get 30 people dancing in unison… and I mean heavy-beat rock n’ roll, not slow dancing to Nat King Cole… and bad things could happen very quickly.

pier 3.JPG

Pier 5.JPG

Pier 4.JPG

Pier 1.JPG

Pier 2.JPG

No building codes in that area…did you call the railings also?

Yep. That and plenty more.


That looks like a good candidate for a stone or timber retaining wall.

True Randy, but then again you can say that for a good many of the homes in the mountains. Part of the problem is that the foundation pads were never dug down deep enough in the first place. Good building practice in the mountains at about 7800 ft. elev. here is to dig down 30" to get below the frost line. These were probably dug down 12" so that the top of the pad was flush with grade on the downhill side.
The home was built in ‘84 but I don’t think the decks were original because the rafters on the back side had been extended (see photos taken inside the soffit… check out the siren in #3!) to create a long overhang to cover the 4’ wide deck back that ran the length of the back side. That made me think that rafters were extended when that deck was installed and both the narrow, rear deck and wide side deck looked to be about the same age.
You can get a feeling for the quality of the foundation work by looking at the CMU foundation wall, which had a significant crack that continued through the footing and showed vertical displacement. Looked to me to be inadequate compaction and homeowner masonry work.

Off-grid electrical was a mess, plumbing was a mess, minimal insulation… buyer passed on it. I did this one on Friday. I thought the seller’s agent would grind her teeth because I called it as I saw it, but today she hired me to do an inspection for her friend.






It doesn’t appear much consideration was given to the piers’ footings “cone of compression” up there, Kenton, a well as the frost line as you said.

Kenton my friend is a contractor up north and they build like that because the municipalities say it is OK. I have yet to see a residential building set up properly after the regarded the slope.
They never underpin dead men and proper shoring to stop land movement on slope of more then 20 percent.
Its just a small link Ken.
They never think of erosion from storms, land movement, and codes are seldom at-teared to.
He moved to Alberta ( Canmore ) avid back-country skier.
They now build on layers of sand, geo-fabric and over sized french drainage.
It still moves and shifts. 1.5 million dollar homes. Wish I had my pics.

Seems to me that link has some weak links, Robert.

  1. There are options for installing septic systems on substrates that aren’t good for conventional systems.
  2. Anyone excavating into a hillside to build a house should expect erosion and have a plan to deal with it.
  3. People commonly build on expansive soil here in Colorado and in parts of California. The foundation is supported by columns going down to bedrock, although I believe that sometimes they drill down to stable soil and bell the bottom of the hole to pour a pad, so the columns rest on pads instead of bedrock. Cardboard void forms are used beneath the foundation walls between columns so that soil has to heave more than about 6 inches before it touches the bottom of the foundation wall. I have yet to see one with void forms fail, but that doesn’t mean they never do.

All three are good reasons to get proper soils testing done before moving ahead with a project.

Pathogens, toxins and undesirable levels of various minerals in well water can vary widely with area. Local health departments are often a good place to ask what to test for. Finding certain filters in a home you’re inspecting can suggest what to tell your client to test for. Looking around and finding the wellhead just downhill from the septic tank can suggest what to test for!
I think a wide spectrum test goes for about $350 here, if I remember (!) right.
In the mountains in CO we see a lot of silt filters, iron filters, water softeners, carbon filters to improve taste, reverse osmisis filters which I think get pretty much everything but environmentally aren’t too good. We see UV filters pretty commonly which are designed to kill anything that has DNA, but because of the high mineral content of the water, the bulbs cloud over and they become ineffective if the bulbs aren’t changed about once a year.
It’s different down on the plains.

Yeah Larry, the cone of compression pretty much ran down the hill with the runoff.

OMG, that is funny. Nice pics Kenton. :smiley:

True Kenton. I though I said a simple link." Its just a small link Ken."
I do not even bother Kenton. It laughable in most regions so I do not even get involved. Sad but true.
Building Monopoly in Quebec Kenton.
Absolute control corrupts absolutely.
Welcome to the Quebec union and there watch dogs.RBQ.
Faught them for 11 years with the CSST.
20 percent payroll insurance for the men.
1 false accident and it went to 35 percent for 5 years.
Do the math on a small 100 large payroll. Small real small payroll. 35 large march 15 before the season. Pay a 21 percent penalty monthly until paid in full.
45 thousand to start a company that made 50 during good times.

That sound like a tough one, Robert.

Sorry Kenton. Theoretical $100,000 payroll.
I did not have the figures in front of me and mine would not reach that.
30 hourly for a bricklayer
17.00 labor
Apprentice mason 20.00 UNION stats you pay that. YOU DO.
I usually used 2 and 3 men and myself the mason . Also did retain walls, cement stairs, walks etc.
I had a crew of 2 to 3 men behind me doing painting window caulk and small stuff.
There company I wanted nothing, not a dine. They had work.

West Island
1 mason= 1 apprentice1 labor= 1 labor last year.=2680= 35% insurance =3828.57 weekly.
40 weeks a year Kenton.Over 150 large.
Over 50% residential builders break the law when paying men and there taxes.
If you make 100 large you are taxed over 50 percent.
50.000 thousand. Biggest year for me was 86 thousand.
Then family came first.

As for the false accident, my payroll was maxed to 34.6xxx percent.
They would not accept photos from me catching him running and walking normal., and it just resolved itself December 10th 2010 and I won after fighting 9 long years.
I won nothing remember but the right to keep my insurance at 17.6xx percent.
CSST in in debt to the Quebec tax payer to the tune of 400 million I believe.
The only insurance company that does not make money.???
And over charges???