We needed to hook up the septic side lines to run from the bedrooms and garage to the main central line coming from under the basement. The original plan had these running under the house, but the plumber suggested that it would be much easier to run the line outside the house completely… At some later point, we also decided to run the bedroom electrical along this outside line. Of course, this all required some digging. Gota love that nice soft sand.
The bedroom septic line had a further run and needed to be below frost depth, so it connected at a lower point on the stack. Then I connected the garage line at a higher point. However, I thought it would be a good idea to slope it more and get deeper than I had to… Some plumbers say that you shouldn’t slope too much because the solids and liquids will separate and you will have clogging problems. I have done my research and determined that was not true (just a plumbers wives’ tale) so I didn’t mind sloping it more. However, after making the stack connection with the Y-pipe shown in the video, I decided that I didn’t like the angle of the connection. Basically, these pipes are designed to connect at closer to perpendicular or maybe 5 degrees off. My original connection was maybe 20 degrees off. It was probably sealed, but it didn’t look great and I didn’t want to take any chances. I ended up cutting off that Y-connection and extending the stack so i could connect at a higher point with less slope.
The plumbing and the electrical in the bedroom wing both connect in the laundry room, very close to eachother so they can exit from the same hole and follow the same trench… However, I didn’t measure conservatively enough and although the electrical cables could reach the panel, I was worried about being a few inches short of making final connections, so we ended up digging a short cut trench for the electrical cables. At least we could still re-use about 2/3rds of the trench.
The Electrical cables:
Earlier, I had experimented with other kinds of cable, running thru conduit. This time I was using cable that was certified to be directly buried. It was still in conduit where it came out of the garage (because it is not certified to be encased in concrete and because I didn’t want a potential leak above the floor anyway), but then came out of the conduit below the footings level. I basically wired it according to above ground code with the required depth below the footing and bushings, etc. After burial, it will only further exceed code.
Just some pics…
The Trench was a combination of had dug and Skid Steer dragged
The Skid Steer can’t dig like an excavator, but it can pull the dirt out of the way with the wide bucket…
The skid steer can’t dig like an excavator, but it sure can move dirt.
Another angle on the SkidSteer, because of reasons.
This is the stubbed in end of the garage septic line that had been buried before the garage floor or footings were poured.
This is the stubbed in end of the garage septic line that had been buried before the garage floor or footings were poured.
The main line is 10 ft below ground. These two side branches bring in the bedroom and garage lines.
The plumbing stack from above.
This is the high end on the bedrooms side. The vertical part was for an additional cleanout. I left it off the video because the plumber didn’t like the angle of the fitting and cut this out before connecting up the way he wanted it.
My father dug most of the shortcut trench himself
Cables laid in the trench…
The boys were mainly for moral support, but still wanted to be in the picture. This picture was just in-case I needed to prove the depth to the inspector.
Another pic for the inspector, with Sherri being goofy in the background while working on the rebar.
This is quite a bit deeper than code requires.
This is the toilet rough in. We simply cut off the pipe and pushed in that fitting so we could attach the toilet.
An inspection is needed before back-filling. Inspections in our township are limited to Monday, Wednesday or Friday, 10:00 AM to noon. And you are required (ideally) to give the inspector two days notice. Sherri and I had already got the waterproofing up and started the drain tile the weekend before, so on Monday, I scheduled the inspection for Wednesday morning and scheduled Roe Brothers Excavation for Wednesday afternoon. The plan was to complete the drain tile on Monday or Tuesday evening, but we had thunderstorms…
My sister (Bonnie) visited us from Canada again, arriving by motorcycle late Tuesday night. I am sure she was thrilled to hear that we would be getting up again at 5:00 AM. We had to get out to the property by first light in order to be sure to get the drain tile in before the inspector arrived.
They call it “drain tile” because it used to be made of clay tiles, curved like Spanish roofing tiles. Now days, it is much better to buy long plastic tubes. Special drain tile PVC is probably better to use because it has smooth walls and lays straight, but I used the corrugated HDPE pipe instead, primarily because of the price and because it is easy to lay around curved walls. I admit that the corrugations are not ideal if you want water to drain out of the tiles completely. I bought drain tile with a sock around it because it was only 5 cents more per ft (it is 50 cents more per foot with the sock if you buy it at Home Depot, so don’t buy it there).
Having to lay the drain tile is a little frustrating because, with all the sand on the site, drain tile is totally unnecessary. We have gone thru many storms in that excavation and have seen that water just falls thru the sand and the water table is not a problem. However, drain tile is required by code. A fellow builder in the same sandy area told me that he put in the drain tile to pass the back-fill inspection, but didn’t actually run it anywhere to drain. Even the building inspector told me that he doesn’t expect my drain tile will ever carry any water.
However, I am the kind of guy who likes to do things right anyway. I spent a lot of time making sure that my drain met the required slope all the way to daylight. This required a lot of digging to lower or raise the ground level.
The building inspector also insisted that we follow the building code requirement to cover our drain tile with 6 inches of pea stone and cover that with landscapers fabric. This would have been great on my current house which is built in clay… Research on the internet showed that it was best to lay the landscapers fabric down first, then lay the tube and gravel and cover it with the other half of the fabric like a very crunchy burrito. The truck delivering the pea stone couldn’t get very close because he was sinking in to our sand (irony?), so we had to carry 4 yards (actually only used 3 of them) down to the footing by bucket.
To make these drain tiles worth all the effort, I decided to use them as bonus earth tubes. This required a change in the layout. Instead of a loop around the house and a single tube draining to daylight, I made it a circuit with both ends draining to daylight… That took an extra hundred and fifty ft of tube that I will run down the same trench as the septic pipe. Actually, I took it one step further and connected the high end of the tubes into my house. Sherri thinks this is a terrible idea because the air traveling thru the tubes could be picking up mold from the corrugations. The fact that it passes thru the septic trench doesn’t help. I think it was fairly low cost and has minimal risk and I can seal it if she turns out to be right.
Back to the Story…
This lugging pea-stone was the fun part that Bonnie arrived just in time for. My wife and boys also carried their fair share of pea stone that morning. The work goes by quick in the timelapse video, but it took several hours in real life. Then we closed the landscapers fabric and waited for the inspector.
He arrived and took a careful walk around. I was expecting him to check the slope, but he seemed content with a visual inspection. I guess it was obvious that it dropped by a ft along the side of the footing. He did comment that my drain tile burrito was strange because most people just lay the landscapers fabric on top of the pea stone, not under it… We passed that part of the inspection.
The inspector was much more concerned about my waterproofing.
I didn’t want to use the stinky tar that is commonly used in my area. It is dirty and smelly and a pain to put up. Other “board based” waterproofing is expensive and much better suited to smooth flat walls. I ended up going with an “elastomeric penetrating sealer”. The install was covered in this post. This stuff sprayed on with a paint sprayer, but quickly soaked in and dried clear… Other than slightly darkening the color of the concrete, you can’t even see or feel it. At a microscope level, it has actually affected the chemical structure of the first quarter inch of concrete to lock out the water… And the elastomeric part will actually bridge cracks to keep them sealed (so they claim).
Anyway, I can’t blame the inspector for questioning a new type of waterproofing that he had never seen before (and still hadn’t really been able to see). He asked for literature on the waterproofing, specifically, if it had passed a certain test. I said I had seen the tech specs on line and they talked about this being for above and below grade waterproofing of foundations and basement walls. I could send him links that evening (in the mean time, Sherri actually got them on her smartphone while on site).
Meanwhile, I had a crew coming to back fill right after lunch.
The inspector decided to give me a “provisional” pass. I could proceed at my own risk. If the waterproofing turned out not to be acceptable, construction would need to stop until I dug it up and reapplied waterproofing so I could pass this inspection. Ouch. But I was pretty confident that basement waterproofing sold at Home Depot would pass. Surely, I couldn’t be the first person to try to use it? Dun dun dunnnn!!!
Back to the Story…
After lunch, the excavators arrived to back-fill. We had made it quite clear that we needed this fill to be well compacted because other footings will go on it. I also marked the 4ft level along the walls and told them to stop at that point so I could put in earth tubes and rigid insulation. They put the sand back in in lifts, each just over 1 ft, and then tamped like crazy with a mechanical tamper.
In this pic, I let my older son go in to help rake even though my wife was very nervous about him being down there while the excavator was running.
Earth tubes have been central to my plan since the beginning. You can see these pages about earth tube design. So it felt great to finally be putting them in. It was also great to have my hard working (and digging gifted) sister to help me out. The primary earth tubes are 8″ double wall HDPE pipe that run over 250 ft down the hill to daylight. They cost about 6 times what the 4″ corrugated pipe costs, but they are stronger, have a smooth inside and 4 times the cross sectional area. The pipe I bought was “earth tight”, rather than “water tight”, just to keep the cost down.
We sloped the pipes at 1/4 inch per ft, which required digging into the freshly compacted sand. The difficulty of digging actually made me feel better about how well compacted the sand was. It took us past dark to get the work done.
This pic shows that we had to cut the pipe and join sections with 30 degree and 45 degree bends. Everything locked together without need for screws.
The next morning, we got Marty (from Roe Brothers Excavating) to compact over the earth tubes for us.
On the other side of the house, we put in shorter earth tubes (average 75 ft) between the house and the window well (as the low point). Here I experimented a bit. I did put in two more of the 8″ double wall HDPE pipes, but I also put in a 6 inch corrugated HDPE pipe and a 4 inch Corrugated HDPE pipe.
Last (and probably least), I put in a 1″ solid pipe (it was actually intended as irrigation pipe). I have had the opportunity to computer model a system for a researcher in India who is working with a system of 1″ earth tubes. His physical model is producing good results so far (he has asked me not to show his results until he publishes his paper). My biggest objection is that the 1″ pipe actually costs about the same as the 4″ pipe, but you would need 16 of them to get the same cross sectional area. There is also the issue of greater back-pressure thru smaller pipes. The benefit is supposed to be much greater surface area, and therefore better heat exchange, so you can use shorter pipes… I am looking forward to the conclusion of the research, but wanted to test my own.
I used hydrolic cement to seal the pipes into the holes I had made in the basement wall. I also filled the area around the connection with pea stone so that water couldn’t sit there.
Back to the Story…
Once the pipes were back in, back-filling and compacting proceeded as before.
At certain times, Bonnie and I laid down Foamular 250 rigid insulation to help trap heat in the volume of earth around the basement. I will talk more about that another time…
The back-filling isn’t completely done, first we need to finish the trench down to the septic tank, and then we can back-fill on that north west side of the house.
Well, it has begun! I will finally be telling my friends about this site so they can follow along. I also created a parallel Facebook page for those friends and family who always stay in Facebook. It also lets me have this cool “like” button on the right hand side of the screen. Since I plan to record and upload videos, I also started a channel for “Simon@HomeInTheEarth.com” on Youtube. I uploaded my first video here…
We still have not closed on our loan, we don’t even have a closing date (we have had 3, but currently don’t have any). On the other hand, construction season is passing us by, so we decided to go ahead with the excavation.
We ended up going with Roe Brothers Excavation. I liked them personally, I liked that they met with me when they said they would and they got me a quote like they said they would. I also really liked the quote. I liked it so much, I was a bit concerned about what I would discover from the references. I was quite relieved when all the references came back very positive. I asked each reference when Roe Brothers had worked for them and they all said, “just a few weeks ago…” It actually took me a week to getting around to calling them, so that is a really good sign that they weren’t cherry picking their references.
Roe Brothers showed up right on time, actually, I got Marty, not sure if he is a brother or a nephew. I’ll ask him next time I get a chance. First, Sherri took care of the initial paperwork and payment. Then we reviewed the bulldozer plan, we discussed which area to level, how deep, and where to push the soil and dirt. They only had a bulldozer on site and said they wouldn’t actually be getting the excavator in that day. It was busy on another job, presumably with another brother? Most of the home is slab on grade, so we still needed to level the site today. But we would need to wait to excavate the basement portion until next Thursday. However, this backed up my schedule because the footings guy was scheduled for next Thursday… I called and canceled the footings, but then at the end of the day, we found out that the excavator will be available by noon tomorrow, so maybe we are back on track? I won’t call the footings contractor back until I know for sure.
On the one hand, my lot is sandy, so it was pretty easy to work with… On the other hand, there was a lot of sand to work with. There was a dip in the middle of the site. We need to go down to undisturbed earth for the footings, so we couldn’t just fill in the dip. Instead, the bulldozer had to get everything down to that lowest level. They setup a laser level at a certain height and then a device in the dozer would tell Marty if he was too high, too low, or just right. I think it took longer (and more work) than Marty was expecting, so it is a good thing that I was on a fixed bid. But Marty was good about it and went out of his way to do a great job. He even cleaned up the driveway slope at the end of the day.
While the bulldozer was busy doing his work, I was busy putting in a couple hundred feet of silt fence. I don’t expect any erosion, but it is a requirement of my “soil erosion permit” and the 60$ worth of silt fence and a few hours of manual labor are better than the $2500 fine for not putting it up. The boys helped a bit. They spent most of their lives hearing that this house was coming, so we took them out of school for the day so they could see the ground breaking. I got some pics of them helping with the silt fence, but it is on Sherri’s camera and I am too tired to upload them now. Instead, here are some fun ones I snagged with my cell phone.
My younger boy is a bit of a Ham.
They really enjoyed playing in the dirt pile during a break.