Author Topic: One Year in a Foam house  (Read 6935 times)

0 Members and 1 Guest are viewing this topic.

zap

  • Hero Member
  • *****
  • Posts: 1107
  • There's an app for that
One Year in a Foam house
« on: August 24, 2005, 05:14:44 PM »
Caveats:  

I'm not trying to push any particular product or practice, this is just an FYI.


My Dad WAS a distributor for Thermasteel which was the main reason for building this house in the first place.


The house up to this point has only been lived in part time.


My Dad has pretty much always lived a low impact lifestyle.


BACKGROUND

My brother and I built this house for our Dad in Pueblo West, Colorado, a city west of (imagine that!) Pueblo, Colorado.  We started it in September 2003 and finished it up with the help of a brother-in-law and various sub-contractors in August 2004.  The exterior walls of the house are built entirely of Thermasteel SIP's(Structural Insulated Panel).  The foundation was fabricated using Polysteel ICF's(Insulating Concrete Forms).  The roof is composed of Actech panels, another form of SIP's, from Alternative Construction Technologies Inc.  The HVAC system is a ground source heat pump from Water Furnace which also provides the hot water.  Three wells were to be dug near the house at 100' each but they hit something hard on the third hole at 50' so drilled another 50' one.


Dad is a Mining Engineer and worked many mines and tunnels in Colorado but moved out of the mountains to Denver and became a General Contractor when mining jobs dried up in the late 50's.  My brother and I grew up in the construction industry but never had much experience with anything from the ground up.  Along with the General Contractor job, Dad had a quite competent framing/finish crew which allowed him to keep tight control over the job from start to finish. Hence, mine and my brother's experience was mostly with wood framing and interior/exterior finish.  Although we had done a little of everything required in the building of this house, this was our first "from the ground up" endeavor.  Bottom line... I would think if you have a modicum of building experience, SIP's and/or ICF's should be easily doable for a self-build.


Enough background, here's the house.



We decided, after watching the ICF distributor build a house nearby, that pouring the basement floor before assembling the block for our foundation was the better way to go.  It offered better support for the 1st floor framing which was basically poured in place while we poured the foundation.



Here the basement slab is poured and the first row of ICF's are in place with rebar installed.  If you get the first row spot on... the rest is pretty easy.  The ICF's we used required either construction glue or foam for assembly.  The distributor we bought from builds up panels in his shop for many of his projects and then trucks the panels to the job site, making for an even speedier build.   Note the vertical 2x's in the corners which help to keep things true.  The foundation ended up 1/4" out of square and 3/4" out of elevation... not bad for a first foundation AND we did not have one single blow out.



The floor joist are Dietrich TradeReady® joist and I was very impressed with the system.  The only problem was that the distributor was new to the system and ordered and shipped almost every joist the wrong length.  They weren't too tough to cut with the sawzall and the package was cheaper than using wood.  You can't see it from this picture but foundation bolts were placed through the rim joist and block every 2' before pouring concrete and in this picture the whole floor is resting on 2x4's running down to the basement slab about every 3 feet around the inside perimeter.  After installing the subfloor, this gave us a nice platform from which to pump the foundation full.



The walls arrive from Virginia and erection begins.  The walls come as a complete package with every piece marked and drawings to show where each one goes.  This house is 1500 sq. feet and the whole package fit in about 1/3 of a semi trailer.  The panels weigh next to nothing, I think a 4'x8' panel weighs around 42 lbs. which is less than one sheet of 1/2" OSB.  We lost part of the front wall to high winds when we left it over one weekend... not enough bracing.  One panel had flown maybe 40' but only one of the panels was damaged and it only required a little foam-in-a-can to repair it.  All in all these panels proved to be quite strong.

Here's a good shot showing how the wall panels interlock and stack.  The Thermasteel panels incorporate a shiplap overlap producing a very strong and air tight structure.  Some of the more complicated panels come preassembled.



Here's the 2nd floor framing.  Except for the main support wall you see here, OSB flooring, and the roof beams, everything is foam and metal.  If I would have been on top of everything, even this wall, would have been metal and just the few studs that went into this wall required culling and even some cutting and straightening before the drywall was hung.  Vendors should really be ashamed of what they try to pass off as lumber these days.



We rented a man lift to assemble the upper parts of the exterior walls so I decided to get a good aerial shot of the whole house.  We also used the lift in place of a crane to install the beams and roof panels.  It worked out well as nothing in this house weighs much.



A picture with the roof panels in place and some more of the upstairs framing.  The "attic" to the upper left of the picture was to be part of the HVAC system but ended up with nothing in it and will be a small storage area.



Here you can see the roof panels where they have been stitched together and down onto one of the roof beams with 10 inch screws.  The hat track on top of the panels was added because the city wouldn't let us install a membrane roof.  OSB was screwed onto the hat track and then roofed as any typical roof.  This added cost/time to the construction but also added an air space which most likely added a bit of R value and keeps the roofing a little cooler.

The finished house.


The house is all electric.  Even now it is still a part time residence, Dad spends 1 or 2 days up north getting the old house ready to sell.  That started in June '05 and before that he spent maybe 3 days a week here.

Here are 1 years worth of electric bills AND MORE CAVEATS.  Dad still does laundry at the old house and there's not even a cloths washer or dryer installed here yet.  Dad doesn't use the stove much and cooks most of his meals using the microwave and toaster oven.  

The community has underground utilities and this lot is big so we had to have another transformer intalled closer to the house because the original run was too long.  The cost of this installation was pro-rated on his electric bill over 4 or 5 years, therefore, his electric bill is a minimum of $68.50 until the installation is paid for, BUT he doesn't pay more for electricity till he uses more than $68.50 worth of electricity.  In other words, he gets $68.50 worth of electricity free till the installation is paid for.

(The billing dates run from the middle of the month, I'll use just the month for simplicity)

Each bill includes a KWH charge, access charge of $6.00, and a minimum billing which I'm not sure of and varies.  The Water Furnace heat pump required 2 electric water heaters, one used only as storage, and this qualified for about $800 in rebates and there may be other rebates for all electric.

DATE        USAGE-KWH        AMOUNT        TOTAL

July 04          191                    $18.27          $68.50(every bill so far)

Aug              218                     20.86

Sept             161                     14.74

Oct              217                     19.87

Nov              465                     42.58

Dec              667                     61.08

Jan  05         513                     53.94

Feb              386                     40.58

Mar              413                     43.42

Apr               253                     26.60

May             333                     36.38

June             409                     44.68


Late fall was cold and this shows up in the bills.  AC should almost always be cheaper than heating this house.  Even though 100° temps are common in the Pueblo area, the ground temperature here is around 57° F.  This house is a good candidate for some type of RE.  I tried to get my Dad to install solar shingles on the south side of the garage but he didn't like the fact that it would "never" pay for itself.  The wind does blow here a fair amount and maybe some type of genny is in the future.


GENERAL IMPRESSIONS

The SIP's and ICF's we used were of very good quality but when you start looking at different systems you'll probably find that most offer roughly the same R value.  Usually you get what you pay for in "fit & finish".  Some of the Thermasteel panels were the wrong size on window and door openings but each required easy cuts using a sawzall (stryofoam and 20 ga. steel studs) and took, at most, 15 minutes each to correct.  The foundation took about 30 man hours to complete and was 32'x25'x9'.  I don't recall how long the wall panels took to erect because of interior framing that also had to be completed as the structure rose but except for the hight, it was easy to build.  The roof panels took 10 to 15 man hours to install.  

The ground source heat pump is very efficient.  Many people refer to them as over-unity machines because they "put out more than you put in".  I was, and still am a bit, skeptical about installing it in this house because the house is already so efficent.  I believe it was 3.5 times the cost of a propane furnace and evaporative cooler and it will take at least a years worth of full time living to see how long the pay off will be.

If I were to build another house I'd really have to look at using ICF's for the whole house.  These make for an incredibly strong and mostly fire-proof structure. The distributor we got the ICF's from said we were his first customers ever to use them only for a foundation.   Another method I'd be very interested in is tilt-up on site precast concrete.  This method produces a structure very similar to ICF's but the end product has all the thermal mass on the inside of the structure.  Naturally there are pluses and minuses for SIP's, ICF's, and tilt-ups but it's a bit sad more of these types of structures aren't being built.


THE COST

I know that's probably the biggest question on everyone's mind.  I've seen quotes anywhere from 1% to 5% more than a stick framed structure.  The only real way to compare the cost would be to build the exact same house on the exact same lot at the exact same time.  Even this would be hard to compare because a SIP structure can be erected so quickly, couple that with weather delays, and you can see how even a modest storm could cause significant time differences between the 2 houses.

Our walls would have cost a consumer roughly $12,000 shipped.  We paid $7,300 for the roof panels which included a bit of a price break on shipping because our panels came from the factory with another load that was dropped off in Texas.  The block for the foundation was about $5,000 and there was block left over that we used for the garage foundation instead of just doing a monolithic slab.  These prices are from mid 2003.  Steel prices soared around spring/summer 2004 and I have no idea where prices stand today.

You're going to save labor cost building a SIP structure and also on jobsite clean up.  We had a 5 yard container, which you can see in the 2nd picture, that didn't see much use till drywall was started.


I hope this post gives some insight and ideas for your next building project.



Editors Note:


This should be a Diary Entry because it is very marginally topical on this forum.


Editor



« Last Edit: August 24, 2005, 05:14:44 PM by (unknown) »