24'x60' garage addition build

[1233user]

I have actually been working on this project for awhile, but have just now started going through the pictures and figured I would post some. The existing garage is 24' wide x 28' deep, the addition part is 24' wide x 32' deep making the total size 24' x 60'. Here are a couple of "before" pictures:



And the back. If you look closely you can see the string marking the footprint of the addition

 

[1233user]

I have a very generous friend who let me borrow his backhoe to dig the foundation trench, all he asked is that I do some minor repairs on it for him in return.



Another friend of mine came over with his laser, so we were able to get the bottom of the trench nice and level.



There was about 18" of topsoil that needed to be dug out, which was a surprise. I ended up with lots of large dirt piles.



Here is the completed trench. Its down at least 42" in all places.

 

[1233user]

I don't know any foundation guys, so I had to hire someone to do that for me. He was in and out pretty quickly. Built the forms for the footing on day 1, then had to wait for the town inspector to look at it:



Day 2 the footing got poured



Day 3 they put up the forms for the walls in the morning, the inspector came in the early afternoon to check the forms, and then they poured the walls that same afternoon.





Day 4 they removed the forms and were done.

 

[rixtrix1]

Why such a wide trench for the foundation? I understand the need for depth.

 

[1233user]

Since the addition part of the floor will have radiant heat, I insulated both the inside and the outside of the foundation walls with 1 1/2" styrofoam.





On the inside, I left the styrofoam 1 1/2" below where the top of the floor is going to be, and I put a 45 degree angle on the top of the styrofoam so the concrete didn't have a weak point right below the floor surface that would possibly crack down the road. The chalk line mark on the foundation is the finish height of the floor.

 

[1233user]

I went back and forth with a couple of different options on how to protect the styrofoam on the outside of the foundation. There was only 1 option that I was really comfortable with, and I knew that I would never have to worry about it again: I had 20 gauge 304 stainless steel sheet metal bent up at a local metal shop, and I installed that around the entire outside. I am very happy with how it came out, and I know that it will last forever.



On the part that bends over the top, I had the metal shop leave enough so it would go past where the anchor bolts were. I drilled holes in the stainless to go over the anchor bolts, and I also put a few concrete nails through the metal and into the top of the foundation. It isn't going anywhere!





As the grade of the yard went down, the stainless went further down the foundation wall so it will be at least 8" below grade in all spots. I put stainless steel pop rivets to hold the pieces tightly together where they overlap each other. The pop rivets are down far enough so they will be below grade and never be seen.



I had already started some of the backfill before this picture was taken.

 

[1233user]

Why such a wide trench for the foundation? I understand the need for depth.

When the foundation guy came out to look at the job (before I had dug anything) he told me to make sure I dug the trench wide enough so he had room to walk around both sides once the forms were up.

 

[rixtrix1]

Guess that would make it easy to set the forms for sure, but what a lot of backfilling/tamping. Have never seen SS used for that purpose. Very creative, and should definitely protect that foam! Wasn't it extremely expensive?

 

[1233user]

When I was at the JCB dealer getting parts for the backhoe, they had a very slightly used compactor there for sale. I had been thinking about buying one anyway because I knew I would need it a lot, and renting one would have been inconvenient. I ended up buying it, this way I won't be rushed with a rental, and I can sell it when I am done with the job.



While backfilling the foundation, I ran the compactor over the dirt every 8 inches on the outside, and every 4 inches on the inside where the floor will be. This compactor does a great job! After running it over the dirt just 2 passes, I had to really work to dig my heel into the ground.





As you can see in that last picture, I built a cap for the foundation to protect the styrofoam and stainless steel. This was last December and I wasn't going to be working on it again till spring. I used "zip" plywood and some 2x lumber for the cap.

 

[1233user]

Have never seen SS used for that purpose. Very creative, and should definitely protect that foam! Wasn't it extremely expensive?

It was expensive, but it was the only thing I could come up with that I knew would last forever. I thought about using aluminum flashing, but I didn't think that would last, and I really hate doing things twice.

 

[1233user]

The next step was to build a temporary wall a couple feet in from the existing back wall of the garage, and then remove the original wall so I could have the back of the foundation cut to get it out of the way.

 

[1233user]

The local concrete yard recommended someone to cut the foundation. They were very professional and did a great job. The demo saw that they used to cut the floor ran off the PTO of the truck. It was fairly quiet, and with the water mist it sprayed it made no dust.



Here is the before picture with the line snapped where the floor cut will be made:





They used a hand held jackhammer to break away the foundation:



And the finished product:

 

[1233user]

Now came what was the most labor intensive part of the job for me, spreading and compacting the process. Here is the first of 2 full tri-axle loads of process:



Before I started spreading the process, I marked the styrofoam and snapped lines all around. I did this so I could do 4" lifts on the fill and run the compactor over it after each lift. The numbers are inches below the top finished height of the concrete floor.



Borrowed my neighbors Kubota tractor to help move the process. I scooped it out of the pile with the tractor, and then dumped each bucket load into 2 wheelbarrows that were inside the foundation, then I spread it with those.





Here is is all compacted after the 1st lift, only 3 more to go:

 

[1949 caddyman]

The stainless will work great. I wonder if you could use cement board like they use for ceramic tile? This will be a nice shop when done.

 

[1233user]

For the top several inches of fill, I decided to use 3/8" washed trap rock. I did this for 2 reasons, first the trap rock would provide good drainage should moisture happen to get in there. Second, the trap rock allowed me to get a almost perfectly flat surface to lay the styrofoam insulation on. Before I spread the trap rock, I put 1 1/2" styrofoam against the existing floor to help insulate it from the new heated floor. I left it 1 1/2" down from the top just like I did with the foundation insulation:



Here is the pile of trap rock:



Spreading it out:



And here it is all finished, leveled, and compacted. It came out really good!

 

[bdkw1]

Very nice!

 

[Nighttrain]

This had to be one of the best back filled foundations I have seen. Great work there!

 

[1233user]

The stainless will work great. I wonder if you could use cement board like they use for ceramic tile? This will be a nice shop when done.

I'm not sure, I never thought about or looked into the cement board. That is a good idea though, and it would have been much cheaper than the stainless.

 

[1233user]

Very nice!

Thank you!

This had to be one of the best back filled foundations I have seen. Great work there!

Thank you! It was A LOT of work, but it was worth it.

 

[1233user]

Next up was the vapor barrier and the styrofoam insulation. For the vapor barrier I used 10mil plastic:



For the styrofoam insulation I used 2" thick, 25psi 4x8 sheets:







All done with the seams taped:

 

[1233user]

Now for the rebar. I found a local company that stocked rebar in 60' lengths. I had them cut pieces to the exact size that I needed, so there are no splices. The floor is going to be 8" thick, so I got 2 1/2" tall rebar stands (they called them slab bolsters) which will put the PEX tubing that will be sitting on the rebar almost right in the middle of the floor. I used 12"x8" spacing on the rebar so it will be easy to do 8" spacing on the PEX. I also put a couple pieces with closer spacing around the perimeter so I can run tighter spacing on the PEX around the outside edge of the floor. I tied every single cross with a wire tie.

 

[1233user]

For the PEX tubing, I ended up using Uponor 1/2" HePEX. I talked to several radiant heat companies about the tubing layout of the floor, and I got different answers from every one of them. The issue was that I want to have the radiant heat from the floor in the addition part to heat the entire garage. I ended up running 5 loops all less than 250' at 8" spacing. I did closer spacing around the outside edges of the floor. I used the program Loopcad to figure out a layout that would keep all the lengths close. Here is the print from that, the 3 spaces with no tubing are for possible future 2-post lift placement:



Here are some pictures with the tubing down:











I notched out the foundation where the tubing exits the floor so that it is as far out of the way as possible:



This is the Uponor manifold and pressure gage. I kept 60psi of air pressure in the system throughout the pouring of the floor.

 

[1233user]

I also put in a short piece of 5/8" PEX to use for a floor temperature sensor. I set this up so it will be 1 1/4" below the surface of the floor, and its away from the rest of the tubing:

 

[dglennon]

Any updates to this project?

 

[1233user]

Any updates to this project?

The garage is up and pretty much done except for a little bit of wiring, insulation and sheetrock. I stopped posting the progress because it didn't seem like there was a lot of interest. I will try to go through my pictures and continue on if your interested.

 

[1949 caddyman]

Yes! We are interested.

 

[colt zantop]

Updates!!! Updates!!

 

[PCO6]

Beautiful job!

 

[ARCTIC_RAGTOP]

Great job on the foundation. Would like to see pics of the finished garage.

 

[farmcat]

very interested in seeing more pics and the progress. Your attention to detail is to be commended

 

[scheu]

Updates? Uh, YES!

 

[1233user]

Ok, next up was the floor. I had all the PEX done and everything ready to pour in the middle of June 2013, but the weather did not cooperate at all. It was either pouring rain, or 90+ degrees. It was the end of July before I finally got it done. It was a very miserable 6 weeks too. I had the area tarped, and with all the rain it kept filling up like a swimming pool. I can't even remember how many times I had to pump it out with a sump pump. Finally there was a day that looked good and I ordered the concrete. A friend of mine came over with his crew on the day of the pour and they brought all their equipment. This day ended up being perfect weather for pouring, it was overcast the whole day and in the 70's. It took about 18 yards of 4500 pound mix with a Super Plasticizer additive that was supposed to help it flow out better

 

[1233user]

I didn't want any saw cuts or expansion joints in the floor, so the whole thing is solid with no breaks. Several people told me that I was going to have problems with cracking if I didn't put any expansion joints in it, but I was totally against having them. I took a couple precautions to keep the floor from cracking as it cured. Immediately after they were done finishing the concrete, I sprayed this stuff on it to slow down the evaporation of water and help it cure slower.



The next day after it was poured I wet it down really good with water, covered it tightly with a tarp, and then flooded the top of the tarp with about an inch of water. It sat just like that for over a month. It is now 2 years later, and there are no cracks whatsoever. I am very happy with how it came out.

 

[1949 caddyman]

Thanks, more pictures please.

 

[stu999]

Very nice job. Just read this thread from the start, thanks for posting.

 

[flyguytki]

keep with the updates, its excellent so far!

 

[1233user]

A good friend of mine is a builder and also owns a Lull lift. I took 2 weeks off from work and my friend the builder, 1 of his guys, and myself tore down the old garage and built the new one in that time. This part went very quickly, but it was a lot of 14+ hour days for me. Day 1 we tore the old garage down, cut it all up, and I brought it to our local landfill in my pickup truck. We did have 1 extra person on the first day helping with the tear down, 1 of my neighbors wasn't working so I volunteered him to help us. We cut the roof into sections, ran a chain through holes we cut, and then pulled the sections out with the Lull.











The lift made things so easy. We just unbolted the anchor bolts holding the walls to the foundation and picked up the whole wall with the lift.





All down and cleaned up after day 1

 

[1949 caddyman]

Do you have a plan that you could post?

 

[kerryt1]

This is awesome. Sorry I missed it the first time. Looking forward to the rest.

 

[yaidunno]

Great attention to detail with the concrete prep work. Please do continue with progress pictures!