Structural Insulated Panels or Std 2x6 construction?

[yeldogt]

I can't think of any house that I have built in the last 20 years that I needed to add an outlet -- some of the worries are manufactured.

In kitchens I remember seeing the cabinets shimmed out with 2x's thick enough to run the pipes and wires on top of the SLP's and behind the cabinets -- so thats a non issue. You have to plan like you would with a log home.

 

[Voi]

Look into advanced ( or stagered framing ) methods using standard stick. You use more studs but but there so damn cheap who cares. This way they do not creat a thermal bridge which is where most your heat loss is on a standard fully insulated stick frame wall. Either 2x6 plate with stagered 2x4 studs or 2x8 plate with stagered 2x6...

I thought "advanced framing" was 2x6 on 24" centers with single top plate, two stud corners and fewer jack/cripple studs?

What you're talking about is using more studs but having every other one to attach the exterior sheeting to and the other set for interior sheathing?

I've heard of that for sound proofing but not as a means of reducing thermal bridging. Off to Google.

Old post but I had to bump it.

[EDIT] Never mind. I think you meant Advanced and Staggered framing as two different options. My bad.

 

[kd3pc]

Many locales will not approve SIPS construction, even with stamps and engineered drawings. Check with your AHJ, BEFORE you get too far down the path.

They work and are so quiet as to almost be creepy. As to adding outlets, there are options and with good panels you can tap in to existing chases, if you have accurate drawings. In my projects, I have seldom added an outlet. There is always a way to add, or use an interior wall or base cabinet. I do leave some spares in great room ceiling to wall ledges and I run a fan outlet in a central location, if possible.

Building with SIPs can be more expensive than stick built, but often pay off in better insulation = lower energy costs down the road. Don't skimp on doors/windows and air circulation as the tight build will leave you wanting, if you take shortcuts with these

 

[Stuart in MN]

My friend who built his house with SIPs (mentioned back on the first page) said it was relatively easy to add outlets. He would cut a square hole for the new outlet box and then use a long cable bit in a drill to go through the foam insulation and any studs hidden inside the SIP. Cable bits are flexible and are used for fishing wires or plumbing, and come in various lengths, Home Depot has this 72" long one for example. http://www.homedepot.com/p/Milwaukee-1-2-in-X-72-in-Cable-Bit-48-13-8350/203115401

 

[NillaRita]

It is a consideration for me if the actual building material is going to inhibit modification of any area in the future, even in a garage. My personal experience is that changing interests modify the way a space is utilized & thus may require additional lighting or power supply availability in different areas than originally planned. I am unfamiliar with SIPS so I am trying to be diligent now rather than run into unforeseen issues later. Your comment about plan like with a log home struck me as a bit scary. That is equivalent in my mind to the foam board basement builds I have seen where it is required to shim out or build out the wall to allow for wiring, plumbing etc. That seems very impractical for a whole structure & must add significant cost to the build. SIPS seemed like a viable, even greener alternative when I started researching them but my concerns & lack of good information out there about actually living with them over the long haul are starting to pose more cons than pros.

 

[Nowater]

My 24 by 36 is SIP, and that is why I often express the value of stopping air infiltration. Also, the components of my garage were tested to 210 mph winds. That is where we will hunker down!

 

[NillaRita]

When I look at the manufacturers sites they discourage horizontal cuts for additional wiring but are not offering information on other ways to achieve it lol. I am sure it can be done as you say by fishing but did doing that undermine the strength of the panel?

 

[Voi]

Thought I'd post a link to a SIP pricing chart. I don't know how these prices compare nationwide.

I assume these prices are just for panels and don't include framing for sill and top plates or any vertical seams that may exist. And of course there is shipping and crane costs.

http://www.acmepanel.com/sip-prices.asp

At first glance it seems expensive but spray foam at a dollar per board foot eats up maybe a third of that cost if sprayed at 2".

 

[kd3pc]

When I look at the manufacturers sites they discourage horizontal cuts for additional wiring but are not offering information on other ways to achieve it lol. I am sure it can be done as you say by fishing but did doing that undermine the strength of the panel?

running wire horizontally is a no-no in any style construction, especially brick/block. Not unique to SIPs. Multiple ups and downs or homeruns to the area you need are the way to go.

In a SIPs/timber frame we did a few years back, the whole electrical was done either in the floors, cabinet kicks or as surface mount on a site built moulding that hid the wires behind a facade. This type of wiring has been used for years in boat building

Fishing does nothing to the integrity of the SIP when you use the chases that are built in at the factory, trying to drill/push through the insulation can be cumbersome, but not much worse than a regular 2x construction wall. The SIP has two OSB/composite panels that provide the strength for the most part.

I would not be at all adverse to building with SIPs if the AHJ allows, keep in mind my last post about air and windows. Some are so tight that closing a door is a chore and will stress the frame if not properly installed.

 

[mikegt4]

I built my house about 20 years ago using SIPS panels and would use them again without hesitation.

I did have some trouble at first with the AHJ (if it wasn't used in the pyramids or the Roman coliseum it was too new to be trusted) but they gave in and since then many other SIPS homes have been built in the area. I built the exterior walls (2 story) with panels then used more panels laid horizontally to form the 2nd story ceiling making a large insulated cube. I used conventional trusses on top of that after placing 2x4's laying flat along the edges of the cube to simulate a top cord for the trusses to sit on. The result has been something akin to a bank vault.

I used floor trusses and have a full basement so access to wiring is not much different than conventional construction. All my plumbing is within interior walls except for the kitchen sink. For that I built a stick wall against the inside of the SIP panel to accommodate the plumbing with the added benefit of no exposure of the pipes to freezing temps.

I can't comment on the cost in today's market although when I built my house they were more expensive to buy, less time and labor to erect so the final cost differential was not that much more. I built the house myself with occasional help from friends so the materials were my only cost.

 

[Stuart in MN]

I built my house about 20 years ago using SIPS panels and would use them again without hesitation.

What's your experience with heating and cooling requirements, and sound deadening? The people I know who have used SIPs say all those things are great, but it's always good to hear more real life experiences.

 

[csp]

running wire horizontally is a no-no in any style construction, especially brick/block.

Yet the standard in stick built is more horizontal than vertical, especially for outlets.

I've seen a wire chase created in SIPs by heating up a steel ball red hot and then it's dropped into the foam insulation, melting a channel from top to bottom to feed the wire through.

 

[romer]

I have been following this thread with interest and think the stick building thing is outdated ; If you look at the David Southey website, http://www.monolithic.org for monolithic domes you will see an alternative.
I live in Saskatchewan and think these domes are the way to go on housing and garages etc. Tornado safe, much cheaper heating, ,cooling, insurance and maintenance costs. As far as I can gather it costs about the same to build this way as conventional.
ICF costs a bomb here, but is slowly being used more. My dream is a dome house and garage one day.

 

[Stuart in MN]

Domes are interesting structures, but the problem is they're round. It can be difficult to make square furniture fit in round rooms.

 

[theoldwizard1]

You bring up a point I had not considered - later wiring. The SIPS I have been researching have the channels for wiring but what happens in these buildings later if I want to add an outlet, additional lighting etc? Is it even possible without major surgery to do that after construction is complete other than doing the wiring on the surface I mean.

If you are building on a slab, going around corners could be an issue. The best solution is install one of more pull cords in the channels while the other wire is being installed.

You might even consider installing large diameter "sweeps" at the corners.

 

[yeldogt]

As I mentioned earlier mine is extremely quiet -- the walls are very thick. It is like being inside a thermos. The frame out I was describing is normally done in the kitchens and baths to make fine adjustments or upgrades easier. Moving and/or adding an outlet or fixture in a stick built house requires just about the same disturbance when all the drywall is finished.

Many converted barns in my area are now using SIP's -- they are attached to the outside of the timber frame and the barn board is then applied to the outside of the SIP.

They have been building with them for enough years that I'm sure most of the normal issues have been figured out. You have to compare them to a very thick walled foam stick built building.

I have controlled conditioned ventilation in mine.

 

[theoldwizard1]

I have controlled conditioned ventilation in mine.

Could you be more specific ?

 

[yeldogt]

In my studio I have outside make-up air connected through a whole house dehumidifier -- it is made by Ultra Air .... the system has a few different ways that it can operate.

I'm a bit north of Philadelphia -- we have hot humid weather in the summer and cooler humid weather other parts of the year. Can't just bring this water laden air into a tight building without some way to dehumidify it.

Its a simple system bringing in outside air when the space is occupied ... much of the time the system is closed and just monitors interior humidity. Because tight spaces need greatly reduced heating and cooling loads -- the A/C may not run enough to remove all the humidity in the summer ... and will not on cooler wet days ... so the dehumidifier takes care of this. In winter you don't get the "stack effect" like you do with other types of buildings that would force air changes - so the system brings in air for ventilation .. but the dehumidifier rarely runs. I also have an exhaust ventilation fan......don't need it often

I have a bit more complicated system for the spray foamed house -- since the house is occupied more often by more people -- the system runs more to provide greater ventilation and to create a slight positive pressure in the house. The incoming air is filtered and conditioned by the dehumidifier (when needed) and returned to the lower areas of the house - or to the HVAC system on the coldest/ driest months.The positive pressure is a good idea in a radon area.

Fantec fans in the baths. The positive pressure is a good idea in a radon area.

I don't like the heat recovery set-ups in my climate.

 

[theoldwizard1]

In my studio I have outside make-up air connected through a whole house dehumidifier -- it is made by Ultra Air .... the system has a few different ways that it can operate.

I'm a bit north of Philadelphia -- we have hot humid weather in the summer and cooler humid weather other parts of the year. Can't just bring this water laden air into a tight building without some way to dehumidify it.

Its a simple system bringing in outside air when the space is occupied ...

So if you are bringing in fresh air, combining it with interior air and then dehumidifying it, don't you wind up with a pressurized house (assuming it is well sealed) ? Do you have vents to let the "bad air" out, besides in the bathroom and maybe a kitchen hood vent ?

 

[yeldogt]

Yes the house will have a slight positive pressure -- the amount of air is small ... and the operation is based on average occupancy .. and any detectable humidity will override the timer.

The system does have a barometric vent that will open when the bath fans go on to allow more air to enter. The stove is connected to a 24v vent damper that allows a lot of air to enter -- that only opens when the exhaust vent is in operation.

It sounds complicated -- but it is very simple .. and most of the air transfer occurs in the lowest level of the house. The correct dehumidifier with enough ports and capacity make it all work -- I use the Ultra Air controller.

I don't make any provision for the small intake air to get out -- I want the positive pressure.

I live in a radon area -- I want the positive pressure so I'm not sucking in any unwanted or uncontrolled air -- especially from under the basement slab.