Scheduled for completion in November 2014, Kamp Kaolin is a high-performance 2,700-square-foot private home on a secluded site in Chester County, PA. HJLCMS collaborated with the homeowners and architect Townsend Moore of Tick Hill Studios. Design and construction for the project are based on passive house principles and building science. Building science focuses on the analysis and control of building materials and building envelope systems. In this case, building science is informing a passive design. Passive houses generally achieve energy savings of 60-70 percent through super-insulation and airtight building envelopes, highly efficient HVAC systems or energy recovery ventilation, high-performance windows, and moisture control. Kamp Kaolin incorporates air and moisture barrier zip systems and super insulation as well as a closed-loop pond geothermal system for extremely efficient heating and cooling. The 2,700-square-foot house also features aging-in-place amenities (roll-in showers, single-floor living), advanced home automation systems (systems and lighting controlled via smart phones and tablets), the warm beauty of timber framing, and integration of indoors and outdoors through an open floor plan with few interior walls, an expanse of windows on the rear of the house that provide pond views, dual rear porches – one open and one screened – and natural, limited-maintenance landscaping.
White PVC pipes run under the slab where the domestic hot and cold running water tubes are housed and run. These plumbing tubes are part of the Hansen House’s wet wall, a structural wall designed to house plumbing pipes for fixtures like sinks, dishwashers, washing machines and toilets. The tubes are connected into the manifold and then distributed throughout the house to the designated fixture. Consolidating plumbing in a single wall increases efficiency as well as cutting down on building costs. The black PEX tubes are for the radiant floor heat which also run to the manifold where the water will be heated by an electric water heater. The PEX tubing was attached to the rebar which was laid out in a checkerboard pattern on top of the foundation’s 4″ of insulation. Then concrete was poured to form the slab. The kitchen island location and outline were marked by tape on the floor for reference points. After the plumbing tubes were all in place, the cellulose insulation could be sprayed. Netting was installed on ceilings and walls to hold the blown in cellulose in place. The netting was used so that the drywall would not have to be installed before the insulation was blown in, which could cause moisture problems. The windows and doors were covered with plastic to be protected during the spray insulation process. Polyurethane, the yellowish material, was sprayed to seal any plywood seams to ensure a tight building envelope. Because the insulation is blown in an excess of material tends to accumulate; therefore, while one person blows in the cellulose another person vacuums it up where it is sent back to the truck and recycled back through the process. The metal braces seen in the picture below are part of the t-bracing which prevents lateral movement. Rigid foam was added to the cavity so that settling of the insulation was minimized and controlled.
Sill seal was installed in between the concrete foundation and the sill plate to reduce air infiltration. Sill seal was installed all around the house. A termite shield was installed between the foundation and the sill plates’ wooden components that are joined to the foundation. The termite shield is a metal barrier shaped in a way that diverts water from running down the face of the wall and eliminates the movement of termites from the soil into wood framing members. The garage was framed out with 2×6’s and engineered framing materials to create open and useful spaces. The 2-car garage also has a back portion that is designated for the homeowner’s motorcycle collection. I-joists were installed in the garage to support the bonus room above the garage. The end of the parallel strand lumber (PSL) beam was cut to create the opening for the stairwell. The PSL beam allows the floor to end so that the motorcycle section of the garage is open to the above. PSL’s are strong and have a high load carrying ability. While the garage was being framed out, the crew started on the rest of the house. The garage roof slopes in a way that adds dimension to the roofline and style to the entire structure. This roofline, along with the motorcycle collection, help define the atmosphere of the garage. The beam in the picture below was salvaged from one of the barns on the property. This is just one of the many reclaimed/found items that the owners wanted our design team to incorporate in the design of their house. The beam was repurposed and used to create the entryway from the foyer into the office.
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.
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.
HJLCMS has been very busy finishing up the KSQ Barn/Carriage Shed. The last update ended with the exterior being prepared for the siding and the installation of the standing seam metal roof. However, before the siding could go on, the windows had to be installed and the electric had to be run. Once the windows were in and the electric had been run, the siding could be installed. The material for the exterior finish is rough sawn board and batten for the first story and a cedar shake for the second story, upper gables and cupola. While this was going on, one of the HLTF crew members was building the cupola in our shop. The cupola was then transported to the job site where it was finished with cedar shakes and standing seam metal roofing. This cupola is not solely ornamental, as it will function as passive climate control as well as house the ventilating fan. The cupola was then flown into place with the crane. Check back for the next update.
Hugh J. Lofting Construction Management Services, LLC (HJLCMS) is currently working on completing the construction of a timber framed carriage shed that had been raised by its sister company, Hugh Lofting Timber Framing, Inc. (HLTF). Once the HLTF crew had completed raising the two-story 24×36 Oak timber frame, HJLCMS took the reins and began enclosing the structure. The frame sits upon an insulated concrete slab, which contains pex tubing for a radiant heat system. This heated floor along with the tightly insulated walls should allow the homeowner a comfortable working environment even in the dead of winter. The 1×10 Eastern White Pine tongue & groove roof decking was the first component of the built up wall system to be installed on the timber frame skeleton. As the decking was going down, felt paper was applied to protect the roof decking from the elements. Once the roof was ‘dried-in’, the interior finish made up of 1×10 tongue & groove, eastern white pine was applied to the exterior side of the timbers to complete the first layer of the built up wall system. The white pine 1×10 T&G applied to the outside of the carriage shed beautifully highlights the exposed timber frame. Once the white pine decking was in place, the rigid foam insulation was then ready to be applied to the entire structure. The two layers of 2” EPS rigid foam board is the insulation for the carriage shed. These two layers are staggered to offset the seams, which will help to reduce air infiltration. Lath, which acts as a nailing surface for the exterior siding, is applied directly to the rigid foam insulation. The added air space from the lath is helpful as it allows any moisture that may find its way behind the siding to dry out. The second story siding will be cedar shakes while the first story will be 1×12 board and batten. In preparation for the cedar siding, the lath on the second story will be installed horizontally across the vertical members creating a breathable lattice framework. The standing seam metal roof is 24-gauge steel with a medium bronze finish. Check back for more updates as the construction process continues.