Westridge Area - Mapache - New Residence

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Project Description

An existing 35-year old house was deconstructed to make way for this new residential development.  A six-week deconstruction process allowed for the salvaging of wood and materials that could be reused in other construction projects.  The existing redwood decking was salvaged for reuse in the new spa decking, while all other wood and materials deemed reusable were transported to the ReUse People in Oakland.

Redevelopment of the site focused on respect for existing site topography and established native vegetation.  The existing house footprint was used for the new residence construction, and the existing pool and shed in the rear yard were removed and replaced by landscape improvements and planting.  Significant existing vegetation, including numerous oaks, was preserved, and new landscaping provides for the enhancement of the native landscape that covers a majority of the site. 

Deconstruction of Existing Residence
Deconstruction of Existing Home

New Residence     Newly Constructed Residence

 

Green Design Elements

Committed to building their home with a greener design and materials, the homeowners found that they had to do much research into the industry on their own and educate not only themselves, but their design and building teams as well.  Their time and effort is evident in the careful consideration of sustainable building materials and design elements that are woven throughout the project, bringing a sense of environmental responsibility as well as a welcoming warmth and comfort to their home.

FSC Certified Wood  The Forest Stewardship Council (FSC) is an independent, non-profit, non-governmental organization that sets environmental standards for timber harvesting.  FSC certified wood is harvested from forestlands that are managed in a manner that is environmentally and socially responsible and have been certified as such by the Council.

The property owners strongly desired to use FSC certified wood wherever possible, and conducted much research and self-education to accomplish their goals.  From the structure's framing to exterior siding and windows to interior finishes, all of the wood used in the project is FSC certified except for the flooring (as there were issues with the use of radiant hydronic heating system).

Framing, Roofing, & Shingles  The contractor praised the use of the FSC lumber for its straightness, workability, and high quality.  "It bends and twists very little, does not have the defects you see in standard lumber."

FSC Framing & Plywood    FSC Cedar Roofing     FSC Cedar Shingles

Engineered Floor JoistsEngineered Floor Joists  Engineered wood is made from smaller trees, reducing the cutting of larger trees that supply traditional joists.  Engineered lumber is typically straighter, stronger, and less likely to warp when compared to dimensional lumber.  You can obtain engineered wood that is FSC certified or that comes from traditionally harvested timber.

FSC WindowsWindows  Low-e, or low-emissivity, windows reflect heat through the means of a thin, transparent coating, keeping spaces warmer in winter and cooler in summer.  These  low-e wood-framed windows are FSC certified.

 

FSC Certified Cabinets & Interior Woodwork  Walnut and mahogany cabinets as well as mahogany columns bring the warmth of wood into the home with the certification that they have been grown and harvested sustainably.

FSC CabinetsFSC CabinetsInterior FSC Woodwork

Indoor Composting ReservoirIndoor Recycling & Compost  Home design includes dedicated cabinets in the kitchen for all recycling and even built-in plastic sack drying racks.  The island countertop has a hole where organic materials can be easily scraped into a plastic bucket below (the pot lid disguises the reservoir).

 

Recycled Stone From Pool Demo and Site Excavation  Stone from the demolished pool was reused on site for landscaping.  Additionally, existing and excavated stone was also retained for landscape use.

Recycled Stone From Pool Demo Recycled Redwood Decking

Reused Redwood From House Demo  The wood for the spa decking was salvaged from the existing house demolition.

Passive Solar Design  This property lends itself to passive solar design, with winter sun shining directly into several rooms through abundant fenestration and skylights, providing excellent natural lighting and warmth.  Deeper roof overhangs block the high summer sun while allowing the warming winter sun in. 

Abundant Fenestration SkylightsDeeper Overhang

Radiant Hydronic ZonesPhoenix BoilerRadiant Hydronic Heating  An advantage of radiant hydronic heat is being able to create heating zones in your home to minimize energy use for unoccupied areas, and radiant heat is much more efficient than forced air.  This home as 14 zones.  The owners chose to use the product Warm Floors™ and the Phoenix™ High Efficiency Boiler.

 

Solar Thermal  Solar thermal panels provide hot water heating and reduce reliance on natural gas.

Spray Foam Insulation  There are many healthier alternatives to traditional formaldehyde-containing fiberglass batt insulation.  Roofing insulation in this home is a bio-based, 2 lb. closed-cell spray foam.  The advantages of a closed-cell foam over an open-cell include higher R-values, strength, and its greater resistance to the leakage of air or water vapor.  Traditional spray foam consists of petroleum oils, plastics, and resins; bio-based foams may use soy bean oil and recycled plastics. 

Relocated Olive TreeNative & Existing Landscaping Preservation and Enhancement  The owners sought to preserve this beautifully wooded site, reusing the original building pad.  Several trees, including this olive, were relocated on the site, as well as these rhododendrons.

 Relocated Rhododendrons

Interior Bathroom TileDecorative Tile  Interior and exterior tile was produced both locally and in Southern California. 

 Exterior Hardscape Tile

 

Q & A:  The Owner's Feedback

Briefly describe the reuse of any of the deconstruction materials/wood in the construction of your new residence.  Where did the rest of the deconstructed materials go?

"We kept all of the redwood decking for reuse in our new deck.  Everything else that was salvageable went to the ReUse People in Oakland."

How long, start to finish, did the deconstruction process take?

"Six weeks."

Who has been responsible for locating the green materials for your project (FSC lumber, windows, insulation, etc.)?

"Both myself and the general contractor.  I have led the way.  I did extensive research on FSC certified wood.  I also insisted that we consider both photovoltaics and solar thermal.  My contractor and my architect did not think solar thermal was worth consideration.  I also took the lead in considering gray water usage (which we are not going ahead with at this time)."

Discuss why you have opted to not use tankless water heaters and what your personal research has revealed.   

"This is the summary of our water heater discussion with our energy engineer:

Tankless Efficiency:  While tankless heater companies claim that their heaters achieve 84% - 89% efficiency, it is believed that because these water heaters all have problems with the build up of scale, after 4 to 5 years, their efficiency plummets.

Expenses:  These units work well for small houses, condos, or apartments, but are expensive for a large house.  Expenses not only include installing several of these heaters in the kitchen and in all bathroom sinks, but they require stainless steel vents and upsized gas lines.

Use of Radiant Heat Dictates Water Tank:  Since we are heating our home with radiant heat (which dictates that a tank-type water heater be used), we will already have a large-capacity water tank, which will be specified to provide us with 95% efficiency.  Since we are installing a recirculating system, which keeps the water circulating throughout the water pipes in the house, we will lose about 5% efficiency.  So our overall efficiency will be about 90%.

Use of Solar Thermal:  Since we are using solar thermal panels for hot water heating, we will reduce our reliance on natural gas as well as our gas bill.  Unfortunately, solar thermal is at its peak in the summer when we do not need it for heating purposes, but it should provide all of our hot water needs in the months when we don't need home heating." 

Did you have numerous green design elements in mind for your project when you first sought an architect?  Or did your architect assist you by providing sustainable options/information as the design took shape?

Originally, our architect did not take the lead in green design.  We chose him because we felt he could design the contemporary craftsman style home that we wanted.  Our architect's primary concern was creating a house that was beautiful and fit our personal needs and desires.  He has done a great job of that.  As the project unfolded, he became increasingly interested in helping us find green solutions.  His roof design (the double roof with insulation between the layers) provided top-notch insulation.

In general, most contractors and tradespeople assume that the home builder will choose a lower-cost solution over a green solution.  As a home builder, I took the lead in asking for and finding green solutions.  My philosophy is that if we can afford to build such an upscale house, we should choose to afford to make it as green as possible.

What particular sustainable design elements were you certain you wanted and would not compromise by eliminating them from your project?

In the beginning, the only sustainable design elements we were certain of were photovoltaics.  We had never heard about FSC certified wood until we attended a green building seminar at Acterra. 

If you were starting from the beginning in developing your project today, what would you do differently?

The main thing I would do differently is to build a smaller house.  Somehow, we didn't realize how really huge this house was.  Nor did we realize that each square foot requires so many resources - cabinetry, flooring, lighting, painting, doors, windows, fixtures...the list is endless.  In hindsight, I realize one of the most important green decisions you can make is to keep your house as small as possible, working to make rooms have multiple purposes.  We love every room in our house, but there are simply too many of them!

I would not have chosen a different architect, but it will be nice when excellent architects have more green experience and can be better leaders in the green design arena.  I did interview architects who specialized in green design.  It was clear none of them was the right person to build a home in the arts and crafts style.  Jon designed a truly inspired craftsman house on a very tricky site.  I wish I could say that if I were to start over again, I would scrap my love for craftsman style houses and build only with green design in mind, then we would have ended up with something like the Jasper Ridge Field Station.  But I do love arts and crafts design and feel fortunate to get to build such a lovely home in its appropriate California setting.  In the end, I feel we had a good team: architect, builder, and me working together to build a beautiful house with lots of green elements.

Do you have any further comments about your choice of sustainable design elements, the construction process concerning these design elements, or...?

Concerning air conditioning, we started out thinking that we would not have air conditioning because, in general, we don't like it and haven't usually felt the need for it.  However, for personal reasons, we then considered wall units for the three areas that we will use the most:  my office, the library, and the master bedroom.  These units have been vastly improved of late, are self-contained, quiet, efficient, effective, and can often be installed unobtrusively.  However, we have put in a ducting system for air filtration, and since we could use that ducting for the AC, the team (architect, contractor, Monterrey Energy Group engineer, and us) decided that it would be more versatile to install a regular AC compressor.  The air conditioning specs for the whole house called for 13 tons of AC capacity.  In the interest of meeting our air conditioning needs with the least AC capacity, we decided to install at 5-ton AC compressor, which serves 4 zones:  office, library, master bedroom, and the rest of the house.  We will not be able to keep the entire house air conditioned to 78 degrees, which is the industry standard target, but we feel with the zoning, we can either keep the three rooms we will use often to a reasonable temperature on those extremely hot days, or bring the whole house to a temperature that would allow people to sleep comfortably at night in an extreme heat wave.  Along with this decision came the decision to use the highest rated insulation so that 

1.  We would rarely need to use the AC
2.  When we did use the AC it would be as efficient as possible

In regards to passive solar, although our house was not designed with passive solar in mind, the site lends itself to passive solar.  We are on a southwest facing hill; the winter sun shines directly in several rooms, especially the kitchen, providing excellent light.  The summer sun is higher, and we are protected from its harsh rays by our roof overhang.  Our site is very difficult, so other than these basics, we did not try specifically to incorporate passive solar.

Other areas of design to consider are kitchen recycling, composting, and appliances.  We have dedicated cabinets in our kitchen for all recycling.  We have a built-in composting hole in our kitchen island.  We have a specially designed drawer for drying plastic bags to make it easier to recycle them.  All of our toilets are dual-flush; they are working well.  It is another area where people can make a difference by their choices.  I am so happy that [the Town of Portola Valley] is starting a green design website so that others can think about these issues before they build and not play catch up during the process.