Design Criteria Part 1

I did a good bit of research for our last house.  I've done a TON of research for this house.  I've spent a lot of time reading articles at www.greenbuildingadvisor.com, www.phius.org, and even purchased a subscription to the Journal of Light Construction (online version).  Even after all that I was still a bit dismayed.

Friends in the building industry as well as owner/builders I have met have filled my head with ideas that I could build a house, even with today's prices for as low as $50 a square foot.  However, these green building sites were talking about affodable homes being built for $105-$125 a square foot.  Something was amiss!

Somehow or another I finally ran across Fernando Ruiz.  He's a builder out in California that has been building for $45-50 a square foot for 20+ years...and still doing it.  When he started it wasn't that difficult as materials and labor were less expensive.  Now that's not so much the case, but he has adapted.  He value engineers his houses and makes wise trade-offs that save him and the people that buy his homes tremendous amounts of money.  And he wrote a book.  Which I bought.  And read.

It turns out simpler plans are less expensive to build.  Two story homes are less to build than single story homes.  One note on that.  Architects will tell you just the opposite.  They say they single story is less expensive because stairs are so expensive.  The two most expensive components of a house are the foundation and the roof and architects are worried about the expense of stairs?  Well I think it just goes to show that what you see depends on where you sit.

Architects, by nature, are dealing with higher end residential builders and home owners.  Massive spiral staircases with lots of exposed wood work are flippin' expensive.  Wrought iron balusters and railings can run up costs in a heartbeat.  A stone or granite staircase might cost as much as my whole house.  That's the stuff architects deal with...pricey stuff.  The rest of us...not so much.  Most stair stringers (the stair stepped structural pieces on the side) in "working class" houses are cut from 2x12's,  Mine will be cut from laminated strand lumber.  They will be covered with carpet most likely.  Even in the event that we do put on a "pretty" tread, it will likely be oak or finger jointed pine.
The first few steps may have exposed balusters, but after that it'll be wallboard up to the top.  I like my stairs a little wider than most so I'll go with a 4' wide stair.  It seems like a small thing and some people will say I'm using too much space with the staircase.  However, I have lived in a house with a 4' wide staircase (our last house) and a narrow staircase (our rental) and narrow staircases suck.  Laundry gets carried up and down, kids get carried up and down, luggage gets carried up and down, half the time someone else is on the stairs while all the carrying is going on (see aforementioned kids)...it's exhausting.  A 3' wide staircase is just too confining for all that activity.

So you can see where builders say one thing and architects say another and they are both right.

Now back to affordable design.  A square is more cost effective than a rectangle, but with the lot we have we want to minimize excavation and that means shallow front to back with some extra width. As I sit and think about it our old house was three different sized rectangles combined.  The first rectangle was the garage area.  The second held the dining area, kitchen, pantry, laundry room, half bath and a few closets.  The third rectangle was the living room, master bedroom, and study.  Our new house will essentially be two rectangles of equal depth.  The first will be the garage and the second will be the structure of the house itself.

Both rectangles will be the same depth and possibly some rooms of the house would be behind the area in the garage (if the garage is 24 wide and 22 deep and that rectangle is 24' wide and 32' deep we could use the extra space for storage or possibly the master closet and bathroom.  

See Ruiz's "Affordability Checklist" to see what you can use on your next project.  Affordability Checklist

Initial Thoughts

House number two is now on the horizon.  It's a difficult lot, a forward facing slope with a significant elevation gain from front to back.  The lot is currently wooded, overgrown, and seems to have been used by neighbors as a dumping ground for their brush and limbs for years.

For this house I have two basic design criteria driving my decisions.  First is affordability.  Houses today are not terribly affordable.  Everyone wants a McMansion, but hardly anyone can afford one.  Looking at the houses of today vs the houses are parents and grandparents purchased two things are evident.  The houses of today are larger and more complex.  If you drive through an older subdivision you will find squares and rectangles.  Houses were smaller and simpler and took up a smaller percentage of the average wage earners paycheck.  Out last house was 2700 square feet this house will be somewhere between 1800 and 2500.

That last number doesn't sound that much different than 2700 but over 600 sf will be "to be finished later" space, and we may or may not build that area in the first place.

My second criteria is about energy efficiency.  If you remember our last house used structural insulated panels, we had all our ductwork inside the heated cooled part of the house, used a marathon hot water heater (a very well insulated electric tank water heater), energy star appliances, and a front load washer dryer set.  All that kept our utility bills reasonable.

This time around we are going to use some different construction techniques to make our building envelope even more energy efficient.  To that end we'll have double stud walls with three layers of R15 fiberglass batts.  We will air seal with acoustical caulk both on the exterior sheathing and the drywall to create a very air tight building envelope.  We will likely use a mini-split unit with a heat recovery ventilation system for our HVAC system.  A heat pump water heater will lead to more efficiencies there and we will possibly use Whirlpool's new condensing dryer to lower energy output there as well.

The subdivision we are building on is not on city sewer so we will have a septic tank.  I've never had a septic tank before, but everyone tells me they work just fine and I have no reason to no believe them.  The thing I am excited about is no more sewer bill!!  Yippeee!!

In the last house our average utility bill (water, sewer, and electric) was $263.  That's not horrible for a 2700 square foot house.  This time around my goal is to lower that to $75.  With no sewer bill, lower heating and cooling costs, lower water heating costs, and cost to operate our dyer I'm hoping that is a realistic goal.