Finnish footing foam…

One of the ideas behind ShopHouse is “healthy”.  Things like indoor air quality are important to us.  We’re spending a lot of time on HVAC, but even the materials in the overall construction are important decisions and opportunities to make sure our indoor environment is the best if can be, as well as making sure that we at least try to choose environmentally decent materials.

Additionally, we’re incorporating a split footing design, where 2 halves of the footing are thermally isolated from on another, and also insulated from the ground (more on THAT project shortly).  So – we needed a source for 4″ xps foam to get the R values we needed AND it needed to have sufficient compressive strength to hold up the house (minor detail).  The search started with the usual suspects – Dow, and other companies that seem to be more chemical that insulation…

And… then we find out that all the foam insulation that appears to be available in the US contains HBCD (Hexabromocyclododecane – there will be a spelling quiz later – so pay attention) – a bio accumulating chemical that is banned in Europe and in the process of being phased out globally.  It’s a flame retardant and blowing agent.  Read the link for a more detailed discussion on why this is bad stuff.

Why would we want THAT all in the ground around our house and under the slab?  It doesn’t need to be flame retardant, and we’re anti – nasty chemical. So intrepid husband starts the search for happy foam to make our footings.

The US companies’ answer for removing HBCD is just to find a better chemical and make everything flame retardant.  Sigh.


In northern Europe, apparently what we’re doing isn’t all that odd, and Finnfoam complies with the stricter chemical regulations of the EU.

So we’re now experts in importing Finnish Foam by the container.  Interestingly enough the cost was equal to the “blue foam” even including ocean freight.  We paid for the foam to be delivered and then unloaded it all into our trailer and basement.

not quite...

not quite…

Another round of my personal slave labor.  That was an entire 40 foot – high cube container…..

Now – on to the form making!

Alexhouse – Personal

Alex - The little dude...

Alex – The little dude…

We’ve joked that we’re simply building a very expensive dog house.  And maybe we’re not joking.   After spending many years doing animal rescue work (specifically Cocker Spaniels- but we’ve had a Chow here and a pitbull there….) you realize that how a dog ages provides a micro level view on how WE age.  The only thing that is different, is that dog’s just “get on with it” and don’t go through the whiny stage.

We’ve had dogs with all sorts of infirmities – deaf dogs, blind dogs, dogs with heart problems, joint problems, skin issues, etc.  They all adapted.  They just go about their day to day routines and adapt.  No complaining, no feeling sorry for themselves – just “being”.  And one particular little dog was extra special.

Alex came into our lives when a client of our veterinarian could no longer care for him.  He was VERY thin, and blind from cataracts.  At only 6 years old – he was far too young to be in such rough shape.  Her office called and said “Dr Grant has a dog for you”…  And so it was.  Alex joined the family.

Turns out he was thin only because the other dog in the house was bullying him for food.  And – one cataract was operable.  The other was not – his retina was shot and it was starting to cause him pain as it developed glaucoma.  So – we did surgery in 2005, restored his sight in one eye, and installed a prosthesis in the other eye.  Alex was visual again.  Sadly, it didn’t last.  After developing glaucoma (more surgery, more meds), detaching a retina (laser retinal reattachment surgery, more meds) we finally lost the battle and he was blind. Permanently.

Honestly- he didn’t care.  He used his other senses to get around, and when he bumped into things, he just readjusted and moved on. We called him our little Roomba. Everywhere around the house, we had / have nose prints about a foot off the floor.  Stainless steel and scrubbable flat latex paint are our friends.

Alex died 2 weeks ago.  Suddenly, and really without warning.  He looked “off” Friday night, I took him to NCSU’s Vet School ER, and he was dead within an hour and a half.

We never anticipated it – he was “only” 13.  We designed the house for our older dogs with various infirmities.  What we found out, is that in doing that – we were using many of the principles of universal design.  THEY taught US.  One level, low maintenance, self cleaning roof, wide hallways, no curb on the shower, zero thresholds at the doorways – all things that would help our little blind dog.  We knew he’d love wandering around in the safe, level, fenced back yard.  And now he won’t.

We’re still shophouse, but we’re just as much Alexhouse.  Rest in Peace little buddy…

Why concrete sandwich panels for our exterior walls? Part 2 – Step 1 toward concrete sandwich panels – the exterior walls

In considering the wide variety of exterior materials that we could use I half jokingly made the statement that I wanted a house built of concrete, steel and glass (design aesthetic #1).  Note that all of these are lousy insulating materials.  So why these materials??  From my personal perspective these were part of the commercial / industrial / modernist design aesthetic (we can call this design aesthetic #2) that I like.  So we asked ourselves why not a concrete exterior to the house??  Properly mixed and cured concrete certainly is a very durable, low maintenance cost material that does not require any exterior finishing as is proven in the millions of commercial buildings that are built out of concrete.  And if it is used without trying to make it look like something that it isn’t then it meets a design aesthetic of “truth in materials” (design aesthetic #3) – it is what it is so don’t try to hide this.  And if we use it this way we get the bonus of not having any additional cost for exterior finishing.

concrete exterior

So how could we execute concrete exterior walls??  Certainly we could do poured in place walls – but these required lots of work in on site forms, dealing with all of the quality issues caused by weather, variations in concrete batches, etc.  Our architect / builder had done poured in place walls on a previous project so they were very aware of the issues with using them.  In particular the waste material from building custom wood forms was an issue.

The next thought was precast walls that could be cast in more controlled conditions that would then be set in place on site.  We looked at these fairly closely and even visited a factory where they were manufacturing walls that had a concrete exterior and were fitted with various materials to serve as studs in conventional walls.  We were convinced that we were on the right track on finding a material and method of making walls that met our exterior requirements – the panels would be “cool” as a way to meet our evolving design aesthetic and accomplish the our exterior durability / minimal maintenance goals  .

Further analysis showed that these panels that we had found still had some issues that we needed to consider.  First, they would still require insulation and interior finishing.  In that sense they solved our exterior goals but not our interior goals.  And they did not achieve the goal of thermally isolating the exterior and interior surfaces – we would still have to accomplish this.  They were clearly a big step away from conventional 2×4 construction – but were they a big enough step away??  Another concern was with this particular company’s ability to execute the panels to the detail and precision that we expected our project to require.

Coming up next – Why concrete sandwich panels for our exterior walls? Part 3 – Step 2 toward concrete sandwich panels – the interior walls

Why concrete sandwich panels for our exterior walls? Part 1

This is the first post from the engineering geek guy for our ShopHouse project.  I will be explaining some of the more technical reasons for the design and material decisions that we are making as a couple for this project.

So why build using concrete sandwich panels for our exterior walls??  There are a  variety of reasons but this decision started as a desire to find a better way to build a house and shop.  And a better way to achieve our goals of having the lowest possible operating cost and the lowest possible maintenance cost.

wood framingI look at conventional 2×4 construction as “lowest common denominator” construction – while it is cost effective I find it to be incredibly wasteful and sloppy.  It also has a fundamental problem that we needed to avoid to achieve our “cooler” concept of thermally isolating the inside of the house from the outside as much as possible.  Every 2×4 creates thermal paths between inside and outside surfaces, thus creating thousands of holes in the thermally isolated “bucket” that we are trying to achieve.

There are certainly a number of ways to reduce the thermal  paths or bridges between the inside and outside surfaces but these add complication and cost to the building process.  One way is to build 2 separate walls so that there is insulation between the inside and outside surfaces.  Again this can give a good thermal result but essentially you are building 2 separate houses, one inside of the other.

Another factor with conventional 2×4 construction is that exterior wall surface materials must be added to project the exterior surface from the elements.  The exterior sheathing, typically plywood or OSB, must be covered to prevent degradation from rain, sun, etc.  There are obviously a very wide variety of materials to use but most are susceptible to damage from the elements and require some level of maintenance.  Brick can be used as an exterior material but you are again essentially building multiple walls in order to achieve the desired end result.

In almost all cases conventional 2×4 construction assumes sheet rock for the interior wall surface.  I find this to be another “lowest common denominator” construction material.  It is very forgiving of construction errors, easy to find people to install and finish, etc but I personally find it to be a material that I would like to avoid if at all possible.  It is messy to install and finish, susceptible to damage from everyday household activities (and especially damage from dogs!), and difficult to hang items from the walls because of its low structural strength.

The net out of wanting to find a better way to build a house is that I challenged the architect/builders that we considered to design a house with no 2×4’s and no sheetrock.  Needless to say the reactions were interesting.  I think that most didn’t believe that I was serious – but at least one took it to heart and embraced the philosophy that this challenge required.

Coming up next – Why concrete sandwich panels for our exterior walls? Part 2 – Step 1 toward concrete sandwich panels – the exterior walls

Congratulations to tonic design

Short diversion here.

Triangle Modernist Houses, whom I have referenced here often, helped bring the George Matsumoto Prize to life.  In it’s second year, the Prize is awarded annually to a Modernist house in NC.  Entries are submitted to a jury of accredited architects and also a public vote is one sixth of the total score.  See the 2013 entries and results here.


Congratulations to tonic design, Vinny Petrarca and Katherine Hogan, on winning this prestigious award for their Rank Residence, completed in 2012.  tonic design continues to carry on their tradition of award winning architecture.  Also congratulations to Michael Rank – who had the initial vision.  Check out this link for pics and also a link to an article in the Raleigh News & Observer for more press on this special home and the design influences behind it.

Rank Residence

I had the pleasure of attending the awards and the NC AIA building in Raleigh.  After a lively happy hour (Thirst 4 Architecture), some crazy infused bourbon, and a talented band of architects – yes – a musical band, George Smart announced the People’s Choice Awards, and then Frank Harmon took over to convey the jury’s placings.  Despite some tough critiques on the entries, and some overall general comments on all the submissions, the remarks about the Rank Residence were extremely positive and fitting the Matsumoto Prize.

Congratulations to the team – and the talent at tonic runs deep.  We’ve chosen well.

One last announcement, Triangle Modernist Houses, is now NC Modernist Houses.  A name change that more accurately reflects the growing geographic reach of the nonprofit organization.

We’re building a cooler.

A cooler what, you ask?  No, a cooler.

The reason a cooler works so well at maintaining the temperature of the things inside it, is that it fully insulates the contents from the ambient temperature.  For the most part (except for the opening lid) there is no thermal path that connects and conducts outside temp to inside temp.  Therefore, your beers stay icy cold!

coolerWhile we might not want to be icy cold, certainly the thermal envelope of any building is the single most important part of the building process, and minimizing the thermal paths, from outside to inside is paramount (as is sealing it up, but more on that later).

Conventional construction – whether 2×4’s or 2×6’s or even 2×8’s have wooden thermal paths every 16 to 24 inches or so.  Therefore, you can stuff some high R value insulation in those spaces, but your still fighting those paths.  Folks have gotten around that but essentially building a house within a house and offsetting the studs, but that seemed, to us, to be a little complicated.  So – what will we use for a wall system?  What can minimize these thermal paths, and is durable and cost effective?  SIP panels?  These are a really good product to minimize the thermal paths, but still very conventional and you still have to put something on the inside of them for walls, and then something else for your exterior finish.

We’d heard about some concrete panels with insulation – essentially the Superior Walls method, but that still wasn’t the answer.  Finally – we found the concrete sandwich panel.  3 inches of concrete, 4 inches of insulation, and then 3 more inches of concrete.  What this did, was allowed the panels to provide our exterior finish (remember – we like the minimalist aesthetic), our insulation, and our interior wall – which we can paint, adorn, or leave in all its grey glory.

Interestingly, this “all in one” material started us down a path for a couple of themes, including one material providing finished inside / insulation / finished outside and also working to minimize the subcontractor on the project to try to contain costs.

So – we now have the walls for our cooler – and we’ll talk about how the insulation could be continuous around the house…..

What do we want?

questionsSimple question, right?  But the answer isn’t the simple.  We knew we wanted an energy efficient home, but “how” energy efficient?  We knew we wanted a Modernist home, but how Modern?

We knew we wanted one level.  Having lived in our current home that is essentially 3 levels – and really only using one – it’s apparent that the other floors are somewhat wasted.  And – since we have dogs – old dogs and blind dogs – accessibility is important.  Having elderly dogs and vision impaired dogs help you learn about things like “aging in place” and accessible (or universal) design.

I am probably more into the aesthetics and the design process than my husband.  He’s definitely into the performance and the materials.  Not to say that he’s not quite particular about design, because he is – he just sees more beauty in a functional design and I might be swayed by anything ‘shiny’…

In working with tonic design, we knew they had recently done a LEED Silver home.  What’s cool about that is that it is the was the first Modernist LEED home in NC.  With basic tenets of modern architecture being lots of light / windows / volumes, it becomes an additional challenge to make these types of homes energy efficient.  It’s pretty easy to make a box with tiny windows LEED Gold or so, but not so easy when you want to use materials like glass, steel and concrete – historically pretty horrible insulators.

As we worked through the design process, we focused on the house and the shop and how we could build efficiently, and how we could make sure that the buildings related to each other correctly and to the site correctly.  The “shop” portion of the project is important to us, so it needed to be fully integrated into the plans.  It was not going to be an ‘outbuilding’ or anything that spoke a different language than the house.

The result is ShopHouse.  A study in glass, concrete and steel that also ends up being LEED Platinum.  Getting that to happen is going to require the right materials and the right team.