The Construction Method
With the ASCEND Together Method, 'low-cost housing' does not equal 'cheap housing'. This is high quality construction.
The ASCEND Method
The building method we intend to utilize, developed by Creating Comfortable LLC, is known as the ASCEND Method. It stands for "Advanced Streamlined Construction with Energy 'Nfluenced Design". It involves super high efficient construction that is simplified for ease of construction and speed, specifically oriented for working with groups of beginners building their own homes. When it is practiced in groups of homes simultaneously it is termed ASCEND Together.
The aspects of the ASCEND Together Method will be discussed briefly below. More information regarding the implementation will be found on creatingcomfortable.com.
ICF (Insulated Concrete Form) construction is utilized because it achieves the goals of the ASCEND Method the easiest. The blocks are lightweight (less fatigue, injury, and more suited for any age), are superior insulation than bay-filled fiberglass systems (no thermal bridging), are easy to assemble with few tools (great for beginners), are stronger than framed systems (by far), provide an air-tight wall envelope without fuss (a huge improvement over stick construction), lend themselves to over-insulation readily, and are much longer lasting without needing to retrofit for a very long time, if ever.
The goal of the ASCEND Method is to provide super high-quality construction in a streamlined way. It is not to make every architect's dream come true. The ASCEND Method calls for rectangular (or square) building envelopes, with the allowance of one indentation (not pop out). Ideally there are no variances from the rectangle shape. This makes the wall bracing required very simple, as well as simplifies the roof system. The simple geometry also lends itself to greater versatility in varying the arrangement of the interior walls and make different configurations available for little/no cost difference.
Simple Roof Designs
The convoluted roof systems of many designs makes them difficult to build energy efficiently, more time-consuming and expensive to install, and require a greater level of expertise to assemble. By using clear spanning trusses, with efficiency heels, it makes an easy covering over the simple wall system. It eliminates load bearing interior walls to allow endless versatility in the interior. Simple roof designs also make the roofing material to be applied much easier and by novice installers. From an energy standpoint, a simple truss system makes the most economical way of achieving a great thermal envelope for the roof.
In-Floor Heating is an elegant solution to many issues with beginner construction methods. Requiring no duct work it eliminates the need for expert tinning skills, no chases or cover framing simplifies interior framing, and it takes no special skills to install. The systems produce an even, comfortable warmth throughout and often even cost less than conventional forced-air systems. They are hypoallergenic because no recirculated dust is being blown about the house. They are also quieter, more compact mechanically, and very low energy to run.
No Roof Penetrations
Penetrations for vents are ugly. Not only are they ugly, they are a nuisance in time, quality, and money to install. They take a clear covered field of roofing and put a hole in the middle of it and try to make it water tight; it's ridiculous. Instead, we tie the plumbing stack vents together and have them exit out the gable end, covered by a screened vent. This makes them invisible and unobtrusive to the roof system. It also makes the installation simpler by not having to cut a bunch of holes in the roof deck or metal sheeting that is used for the top surface.
Standing Seam Roofing
A roof system's job is to keep the structure dry and protected, and worrying about that ever being an issue does not bring any sense of comfort. Thus, a durable long-lasting, fool-proof (or at least fool-resistant), and attractive method should be employed. Standing seam metal roofing, with click-lock seams, require no special tools and have no revealed fasteners. The colors last 35+ years and the metal often longer. Fast to install, great for beginners, and longer lasting, they are a great choice for a roof. Particularly a simple roof with no hips or valleys to run amok and cause trouble!
Windows are the bane of the thermal envelope's existence. They are the weakest link to energy efficiency and thus it takes great care to make the most of this problem child. All 'American' sliding windows are out! Sliding windows using bristles for air sealing never achieve sufficient air-tightness and only get worse with age. Employing positive sealing casement, hopper, tilt-turn, and tracked sliding windows are the only acceptable option. We also prefer triple glazed, European windows for their hardware quality.
By attaching additional rigid insulation on the exterior of the homes, it serves to increase the energy efficiency, as well as reduce bracing requirements of the ICF wall system. By using 2+ inches of EPS sheets pinned on by 1x4 furring strips anchored to the ICF wall, the panels stiffen the wall plane to reduce any waving walls and make the wall plane easier to brace. (It also provides a gap and rain screen, so adding reflective foil-backed EPS will get another r-2.8 or so).
Air-Tight Attic Insulation
"Make it air-tight, then ventilate right" is the building scientist's mantra for comfortable and efficient housing. To air-tight the ceiling portion of the thermal envelope we apply gypsum board to the ceiling BEFORE interior walls. Then we install interior walls and run electrical lines. After electrical boxes and fixtures are roughed in, we spray just one inch of spray polyurethane foam insulation over the entire attic side of the gypsum board and truss bottom chords. We extend that air barrier up the heeled trusses with baffles as backing. This makes an excellent air seal that is the first key to good energy performance.
Designing for the future, or anti-obsolescence design, considers the full life cycle of the structure and its users. For homes that cater to all ages, minimizing or eliminating stairs, keeping adequate widths, and eliminating thresholds is important. We utilize dropped or zero-entry thresholds for all exterior doors. This maintains wheelchair accessibility, as well as reduces trip hazards. We also eliminate all steps for single level units. All shower pans are dropped, rather than raised, with roll-in shower entries.
Fiber Cement Cladding
Cladding, like roofing, protects the envelope of the house from the elements. Exposed for decades in the elements it takes quite the abuse. In order to mitigate maintenance, repair, and deterioration, a high quality siding is used. We prefer fiber-cement siding for its aesthetic appeal, simple installation, as well as its 40+ year lifespan. It also is fire resistant, hail resistant, and comes in various styles and is available pre-painted or pre-primed then painted on site. Very versatile and high quality, it makes a great exterior.
In an effort to make quick, long-lasting, and aesthetically pleasing homes, stone work makes another good option for exterior cladding. Cheaper options, but more classic and hard to install, are artificial stone with standard masonry practices. We prefer a little higher price point in favor of simple installation in the form of adhesive applied, or screw applied. This allows beginners to assemble the products quickly, and some models are more protective than standard masonry. (SilverMine Stone)
Stained Concrete Floors
Since the foundation of the home is made of concrete anyways, it makes good sense to use it at the finish floor to save on adding floor covering costs. By staining and sealing the concrete it produces an attractive, low maintenance, and durable floor system at a fraction of the cost of typical floor coverings. The staining and sealing process is about ($.80/sqft). The level of finish does cost a little bit more for the concrete finishing, but saves a lot of money in the long run. It's also nice because you can easily cover it other coverings if ever desired without any tearout.
The cost of light-bulbs in the era of technology has made it just as easy to supply a house with long term energy savings and go with LED at the beginning. The lifespans of the bulbs easily compensate for the extra expense in the initial installation. This in turn brings down the energy usage and allows for smaller solar panel installations. They also make the light quality more variable and on-demand. Use of LED bulbs also decreases maintenance time overall since the frequency of replacement is greatly reduced. LED's slim profile also make them a versatile lighting option.
The misnomer that a 'house needs to breathe' is really a way of saying the occupants need fresh air. Having an air-tight building envelope is cause for trouble if a proper ventilation system is not installed to counterbalance it. An Energy Recovery Ventilator or Heat Recovery Ventilator is necessary to maintain good Indoor Air Quality (IAQ). They work on the principle of having an exchange box that helps energy transfer between air flows (without mixing), thus reducing the energy required to condition new air but still providing fresh air to the indoor environment.
A Frost Protected Shallow Foundation (FPSF) is one of the ways of simplifying construction and eliminating one of the technically complicated parts of the construction process. Only necessary in places with frost depth, FPSFs allow for just a 16 inch deep excavation and therefore an insulated slab on grade construction. It eliminates working up and down ladders for the foundation work, most dirt work, and provides the intrinsic benefit of insulating the house from the earth by means of rigid under slab insulation. It is a value-adding alternative to frost depth footings which solve the frost issue, but don't add any value for the homeowner (and cost more).
Orientation and Shading
While it isn't of paramount importance in most cases, it is still important to consider how the orientation of the structures interact with each other and the environment. Maintaining appropriate overhangs and screenings can block summer sun while still allowing winter sun to heat the homes. Deciduous trees can provide shade in summer, and let sunlight through in winter. Southern windows and doors can serve as warming walls to reduce heating requirements. In conjunction with proper glazing technology, the orientation of the structure, intelligent fenestration placement, well planned landscaping, and intentional architecture can do more than add aesthetic appeal.
One qualm some people raise about near neighbors is a sense of privacy, or lack thereof. One of the design elements incorporated in close-proximity neighborhoods is nested design. The windows and doors of one home look upon the closed walls and screened sides of the neighboring house. This allows a tighter clustering, thus increasing land-use efficiency, while still providing the sense of privacy that one would expect in a 'single family home' neighborhood. With important details like nesting accounted for, it's possible to still feel very comfortable even with the neighbors much closer than the typical residential homeowner is used to.
Cellulose Attic Insulation
The cost of insulation does not have to be expensive to be effective; it needs to be intentional. Cellulose is preferred over fiberglass mostly on its recycled nature, handling of humidity, and is nicer to work with from a comfort standpoint. Other large fill insulation options are also fine, though. Unless located in fire-prone areas, it is needlessly expensive to do sealed attic spaces. Sealed attics also pose concerns to address. Insulating directly to the roof deck can cause hot decking, ice damming, and let wood rot go unnoticed. This can be mitigated by another air flush layer, but it's just one more thing to add. We prefer to be simple and fill in the well-vented attic with cellulose.
Proper Attic Venting
Sealing the ceiling plane with SPF, as well as the heels of the raised trusses, encapsulates the insulation so it isn't just a large air filter. It greatly reduces convection in the insulation so it behaves as a thermal insulator as intended. To prevent issues with humidity, ice damming, and hot decking, the underside of the roof deck needs a constant wash of air. This is provided by copious amounts of soffit venting as well as sufficient ridge, and gable venting. Other top vents work, but are ugly and are failure points, so we only vent with ridges and gables. This is used successfully everywhere but not suitable for fire-prone zones. They need sealed/unvented attics.
Tankless Water Heater
Technology has come a long way since the Civil War, but judging by most house construction, you couldn't tell all that much. Tankless water heaters are an innovation that make great sense for just about everyone. They have a smaller mechanical footprint, very simple installation, longer lifespan than tanked heaters, use less energy, and cost about the same. The Takagi water heaters we use heat the in-floor radiant system as well as the domestic hot water in a low-tech open loop system that is inexpensive and low maintenance. Taking up the space of a small closet makes them even more ideal for small or single level homes, particularly where no basements exist.
American styled cabinets, also known as face frame cabinets, waste space and are more expensive to build. European styled cabinets allow for greater versatility in cabinet hardware, drawers, better hinges, faster install times, and lower costs. Looking nearly identical to the average consumer, the appearance is much less a factor than the performance. The melamine interiors are much more water resistant and have become the standard for custom homes and commercial use also. Available through flat pack options, like Ikea, or through local cabinet shops, this is a great upgrade that saves money.
Solar panel technology has come a long way. The photovoltaic cells are more efficient, the inverters, batteries and other equipment are also keeping up. Solar hydronic panels are also a great option, particularly in places that the floor has in-floor heat. In clustered neighborhoods with common buildings it makes good sense to orient the roof line so the southern face can be fitted with panels to supply for the whole neighborhood. Larger, clustered banks, take less installation cost. It also allows for more versatile orientation of the smaller houses by not having to worry about their southern exposure.
While it isn't necessary to account for this intelligent feature, the ASCEND Method does recommend it. Driveways, parking lots, and areas desired to be free of snow and ice should face the sun. It's simple, but most people just build and throw in a landing strip as an afterthought. Even a few degrees of sunlight make a huge difference in the workload to keep the snow and ice at bay. Also consider sun reflections from other buildings/objects as this can increase the effectiveness of the sun's rays to expose solar radiation around corners where otherwise it can't reach. It's simple, but can make a big difference.
The ASCEND Method is different than typical ICF construction in the unique way it uses over-insulation. By over-insulating with thick rigid EPS foam, and attaching that via batten strips, it creates a very solid plane with the empty concrete forms. While most people would brace the walls as normal and then add the insulation after, we insulate and batten the wall to hold it in plane, thus helping to reduce the need for bracing so frequently. This eliminates the time and effort of no-value-added labor on the project. Since the insulation serves as insulation and partial bracing, it adds value and trades some labor cost with more insulation, rather than just spending on bracing installation and removal time.
While it isn't viable in a lot of construction scenarios, bulk ordering can be greatly beneficial if it is able to be done. If forming a cluster of homes, consider building them in phases simultaneously rather than staggered phases. Greater discounts, saved shipping costs, greater priority scheduling from suppliers, and more can be realized by building several projects simultaneously. It's more efficient to build in bulk; so do so when possible. Even on stand alone homes, try to order materials at the same time for various projects to harness greater buying power when possible. Conventional construction financing may not allow for much leeway depending on the lender, but try to bulk order as much as possible.
Proper Window Install
A good wall and a good window are great, but attached via a shoddy interface that deteriorates too quickly is just an embarrassment to the whole scenario. Take the time to properly air-seal the fenestration edges so they perform properly for the long haul. Spray in place foams shrink and crack; make sure to have another layer beyond those alone to make a quality attachment detail. Tapes, caulks, liquid applied water and air proofing; they all have their place, and it's important to take the time to satisfy all the purposes of the connection. Fixing issues is too expensive to short-change this step. Just bite the bullet and do what it takes to get it done right!
Another important component of streamlining ICF construction, and making it more adapted to beginners, is by eliminating splices. The sizes of the structures using the ASCEND method are specifically designed to be built without any cutting of the blocks, except for doors and windows. The entire perimeter is sized around the block. In our case we use 4' long blocks and therefore work in 4' increments. The houses are planned to be stacked entirely together with running-bonds the whole way around. This helps reduce bracing, makes it simpler for beginners, and helps maintain plumb corners and walls.
Advanced Framing is a somewhat general term, but specifically refers to optimized framing methods. There are no framed load-bearing walls in the ASCEND Method, but it makes sense to have what little framing there is to be optimized. This includes using either metal studs, or at least 24 On-Center (o.c.) spacing. Metal studs have the benefit of being user friendly for beginners with just tracks and screws/crimping. Also, they are always straight, and you can maybe save space by using a narrower stud than 3.5 inches. Sometimes inches matter in small spaces. 5/8" drywall can help cover 24 o.c. studs.
To make sure there is no funny business on the long standing, inconvenient-to-replace aspects of the building, such as the roof assembly, more material cost is allocated towards it. This includes uses a slightly thicker sheathing than is typically required. We employ 5/8" OSB, or plywood. Often-times the cost is considerably cheaper for OSB and is more dimensionally stable, so it is most common. Thicker sheathing prevents sagging between trusses, and make for a more resilient roof system. In heavy snow load areas, it makes good sense to call for it.