The Hansen House Part 3: Concrete Slab/Radiant Heat

The month of July has been very busy at the Hansen House.  Once the insulated foundation was complete the plumbing pipes, as well as mechanical conduit piping, were laid out, run and installed. Plumbing pipes have to be run at a slight downhill slope so that the waste in the pipes can drain properly. Weld-On P-68 primer was used to help join the pipe and fittings.  This low VOC product is compliant with LEED Green Building Rating System and can be credited towards indoor environment quality. The same GreenGuard rigid insulation that was used with the foundation walls was installed before the slab was poured.  These products contain up to 30% post-industrial recycled content and help reduce energy consumption and improve durability. On top of the 4 inches of insulation the rebar was laid out in a checkerboard pattern used to reinforce the concrete and prevent cracking.  The PEX tubing for the radiant floors is also attached to the rebar structure. PEX tubing is a tough, flexible plastic that is easy to layout in loops and bent around corners.  The PEX tubing is where the warm water is circulated to heat the radiant floors. Select floors throughout the Hansen House will have radiant heat.  The PEX tubing for the radiant heat will run to the manifold in the mechanical room.  Here it will be heated with an electric water heater and pumped back through the piping.  The electric water heater will be run on energy generated from future solar panels. The concrete is then poured over the PEX tubing and rebar. Using products made from recycled materials is a standard operating procedure for HJLCMS.  The concrete for the Hansen House was made with 20% fly ash and is sourced locally.  This recycled material content is closely tracked should the need for LEED certification be considered. Fly ash makes the concrete more durable, water-resistant and stronger.  Fly ash shrinks the environmental footprint of concrete because it reduces the amount of water and Portland cement in the mix. Once the concrete had set, the power trowel was run over the surface to smooth out any imperfections and get a tight, glossy finish.  The more passes with the power trowel will give you a more glossy finish. The broom finish on the concrete floors for the wrap around porches gives a unique and distinguishing feel to these outside areas. A material called River Jack was added to the concrete as the aggregate giving the East porch a textured surface. Check back for the next post as the crew begins to frame out the garage.

The Hansen House Part 2: Foundation

Since HJLCMS broke ground on June 1st on the Hansen House, there has been a lot of progress on site.  We wanted to make sure that none of the trees were unnecessarily disturbed by the construction process so signs were placed at drip lines of the trees to protect the root systems. The new driveway was engineered to share a portion of the existing driveway to reduce the footprint of new construction.  Gravel was used because it is a permeable surface that allows rainwater to be absorbed and therefore naturally filtered. Once the driveway was complete, the crew excavated the area for the house and dug out the footers. The Hansen House is designed as an energy-efficient building.  One of the keys to an energy-efficient building is the use of high levels of insulation.  The concrete footers and block foundation both contribute to the super insulated slab and insulated slab ledge. Because heat is lost through foundation walls and concrete slabs, it is important to insulate them.  There is 2” rigid foam insulation along the perimeter walls of the block foundation.  The foundation is part of the house’s thermal envelope.  A clear penetrating sealer has been applied on all perimeter walls from the footers to the tops of walls to damp proof the foundation.  The insulated foundation contributes to the conservation of energy and heating and cooling costs and also eliminates potential moisture and mold problems. Check back for the next phase of construction.

Introducing The Hansen House

Introducing the Hansen House – HJLCMS’s newest project. On June 1st HJLCMS broke ground on our newest project in Chester County, PA, the Hansen House.   This is one of the several projects HJLCMS has going on during this busy spring and summer.   In line with the mission statement of HJLCMS, this project will be built around sustainable systems incorporating the highly energy-efficient green technology standards we at HJLCMS hold ourselves to. In the early stages of planning and siting the Hansen House, HJLCMS and the Owners performed a careful evaluation of the solar access, water resources, vegetation, soils and other important natural areas of the site.  The information they gathered helped to guide not only the actual location of the house but also some key design elements of the house.  For example, the house is designed to utilize passive solar heating, day lighting and natural cooling.  Because of this careful planning, there has been minimal site disturbance and all the topsoil will remain on site to be used later in the construction process. Make sure to check back soon for our next post on the Hansen House!