"Building green costs too much." "I'd like to include green features, but the budget just isn't high enough." "Green building is just for wealthy clients." All too often we hear these claims. And, indeed, a lot of elements of environmentally responsible building do cost more - at least in the short term. But many of the design and building practices that are described in the pages of EBN (Environmental Building News) or advocated by a growing cadre of environmentally conscious designers and builders cost no more than conventional practice. Indeed, some cost less.
We're talking about first-cost here - how much more (if any) it costs to incorporate green features into a building project. Life-cycle costs are different. When we factor in energy savings over time, or increased durability, or enhanced worker productivity, green design features and materials become much easier to justify. It would be wonderful if life-cycle costs were considered as a matter of course in building design today - but they are not. Most of us in the building profession are forced to deal almost solely with first-cost in justifying our projects.
To address this issue - and the perception that building green has to cost more - we're devoting our feature article this month to low-cost green building features. Most of the article is a checklist of design strategies, building practices, and material substitutions that will cost no more than - or actually cost less than - conventional practice. By no means should this list be considered complete in terms of what can be done on a tight budget. With good integration of all the disciplines on a design team, it is possible to incorporate, within budget, many strategies that taken alone would increase costs.
Some Cautions on a Low-Cost Agenda
As we examine green design strategies and construction practices that reduce (or at least do not increase) construction costs, it is important to point out that limiting oneself to only those strategies that keep first-costs low may not be in the best long-term interest of the client. Sure, we can create better buildings (from an environmental standpoint) while spending less money, but realize that too strict a policy on avoiding those strategies that increase first-cost may result in lost opportunities for even more significant savings down the road. Yes, we should pay attention to low-cost strategies, but we should also pay attention to some of the higher first-cost strategies that can significantly reduce life-cycle costs.
As the green design field matures, it becomes ever more clear that integration is the key to achieving the energy and environmental goals we desire - especially if cost is a major driver. Integration is more than using the savings from one change to pay for another - it's about making changes that allow other changes to happen. A smaller chiller, for example, makes money available to upgrade the envelope, but it also depends on the envelope upgrade to satisfy the building's needs. While integration can keep construction costs down, it usually requires more time to be spent in up-front design. - Alex Wilson
Renovate older buildings.
When we renovate older buildings instead of building new, we generally save significant quantities of materials and energy, thus benefiting the environment. In addition to reducing project costs, there may also be significant savings in time and money associated with not needing as extensive regulatory review and approvals.
Integrate the planning and design process.
Integrated building design can often result in first-cost savings. This is certainly the case with energy design (see below), but savings can also be achieved in other areas of building design through careful integration. For example, including the general contractor in early discussions with the architect and engineer may identify ways to streamline the construction process. Involving a landscape architect early in the site planning process may reduce the need for (and cost of) plantings by identifying ways to protect what is already on the site.
Create smaller buildings.
Smaller, more space-efficient buildings require fewer resources during construction, disturb less land during sitework, and use less energy during operation. Depending on the design, the total cost is generally lower, though the cost per unit area may be higher.
Look for opportunities created by regulatory hurdles.
Regulatory obstacles often pose significant challenges to green design, but they can also provide opportunities in some cases. For example, if a regulatory body proposes that you spend a lot of money to put in a stormwater detention pond, that presents an opportunity to do something better - like porous pavement, reduction of impervious surfaces, rainwater catchment, and infiltration basins. The alternatives may well be less expensive, more environmentally responsible, and ultimately more palatable to neighbors and planning officials.
Optimize orientation.
When feasible, site a building to optimize solar orientation and access prevailing breezes. With houses, locate more of the windows on the south than other orientations. It costs little, if anything, to reposition windows and modify the orientation moderately during design.
Minimize east- and west-facing windows.
To minimize cooling loads in houses, reduce the area of windows on east and west facades. By installing fewer windows, costs should be lower.
Leave floor slabs exposed.
Rather than carpeting a floor slab, leave it exposed. Molds and other biological pollutants will be avoided, the environmental impacts of carpeting will be avoided, and the cost of carpet can be avoided. There are many options for attractively finishing concrete slabs, including texturing and pigmenting. Most (not all) of these are less expensive than carpeting.
Eliminate dropped ceilings.
Savings can often be achieved by eliminating dropped ceilings. Pendent light fixtures, additional painting, special fireproofing measures, and exposed ducts will usually be required, offsetting some of the savings, but other opportunities may open up as well, such as deeper daylighting penetration and, in some cases, reduced floor-to-floor height (which can reduce overall building dimensions).
Avoid structural overdesign.
Optimal-value engineering (OVE) and advanced framing are strategies for reducing material use without compromising structural performance. By reducing material use, these practices reduce resource use while saving money.
Provide open layout.
Provide an open room layout in buildings to facilitate distribution of natural daylighting, reduce ducting requirements for conditioned air distribution, simplify the reconfiguration of space, and reduce material use. Pay attention to sound control.
Optimize material use by standardizing dimensions.
Anytime we reduce cut-off waste or use less material because we have optimized building dimensions, we save both resources and money. In reducing waste we save money several ways: by buying less material, by reducing on-site labor (for measuring and cutting), and by paying less for solid waste disposal.
Save water
Save water. There is usually little, if any, additional cost associated with substituting water-efficient equipment. Waterless urinals, for example, eliminate the need for water supply piping.
Cluster buildings.
By clustering buildings and preserving larger areas of open space, we reduce the costs (and environmental impacts) of pavement, sewer lines, utility lines, stormwater system, and so forth. The open space also serves to protect local ecosystems and biodiversity.
Select sites that make use of existing infrastructure or that require minimal extension of infrastructure.
Where roadways, water, sewer, and utility lines are already in place or require minimal extension, the infrastructure costs of development can be significantly reduced - while the environmental impacts of development are reduced and more pristine, undeveloped land is preserved.
Manage stormwater responsibly.
Conventional practice with both residential and commercial developments is to carry stormwater off-site in storm sewers. A better approach is to allow that water to soak into the ground to replenish aquifers and reduce downstream flooding. Carefully planned infiltration basins and measures to reduce impermeable surfaces are generally less costly than conventional practice of storm sewering and building large detention ponds. Examples include: avoiding contiguous impermeable surfaces, minimizing roadway width, and using porous paving materials. If stormwater must be collected in storm sewers, design systems to minimize transport of that water and release it within the same drainage basin.
Minimize paved area.
Minimizing the driveway or access road length to a building reduces impervious surfaces, helps preserve open space, and reduces resource consumption - all while saving money. Also keep streets and driveways narrow, and look for ways to reduce parking area requirements. The latter might be done in commercial building projects, for example, by convincing the company to offer employee incentives to use public transit.
Avoid cut-and-fill.
In site planning and grading plans, avoid or minimize cut-and-fill practices that either carry soil off-site or bring soil onto the site. Restrict cut-and-fill to on-site movement.
Protect existing vegetation.
It may cost a little more to protect existing trees on a site, but that cost can easily be recouped through having to spend less on plantings following construction. Large trees around a new house may also significantly boost the property value. Protection of shade trees can allow downsizing of air conditioning equipment, because cooling loads can be reduced.
Use native plantings.
Indigenous landscaping (prairies, woodlands, desert gardens, etc.) support wildlife and biodiversity far better than conventional turf. Native landscaping also does not require irrigation and chemical treatments (fertilizer, herbicides, pesticides, etc.). In most cases, it costs less to landscape with native vegetation than to put in lawns, though costs are variable.
Use xeriscaping practices.
In areas with low annual precipitation and areas that are prone to droughts, provide xeriscaping (dry-adapted plantings) to obviate the need for irrigation systems and more expensive plantings.
Provide an integrated energy design.
By carrying out integrated design, it may be possible to pay for increased efficiency measures through savings in HVAC equipment. For example, a tight, well-insulated building envelope with high-performance glazings and shading strategies may enable you to significantly downsize - or even eliminate - conventional heating and/or cooling equipment.
Model the building.
During design, model the energy performance of a building so that mechanical systems can be optimized. Conventional practice is to oversize HVAC equipment, which wastes a lot of money.
Tune glazings to orientation.
There is usually little if any additional cost in specifying different glazings for different orientations. In houses, low solar-heat-gain-coefficient (SHGC) glazings should be used on east and west orientations, for example, while high SHGC glazings make sense on south orientations when passive solar and daylighting are being utilized. In commercial buildings, low SHGC glazings may be appropriate for south-facing glazings as well, because cooling loads can be high even in the winter, when the sun is low in the south sky and heat gain from the south is significant.
Consider access floors.
Access flooring offers opportunities for energy savings, improved indoor air quality, easier reconfiguration of spaces, and - often - reduction of first-cost. (See EBN Vol. 7, No. 1.) Construction costs are most likely to be reduced if integrated design with access floors enable savings elsewhere (elimination of dropped ceilings, reduced floor-to-floor height in multi-story buildings, reduced cooling of underfloor supply air, faster construction, etc.).
Expand the comfort envelope and downsize cooling equipment.
By providing operable windows for natural ventilation or ceiling (paddle) fans to increase air flow in buildings, occupant comfort can be increased with less cooling than is typically required. Reliance on such practices can permit downsizing of mechanical cooling equipment, reducing equipment costs.
Do not run ducts to exterior walls.
Keeping ducts away from exterior walls will improve energy performance and save money - because less ducting will be required. Good energy performance of the building envelope is necessary for this to succeed.
Consider a water heater for space heating.
By reducing heating loads in a house, it is often possible to satisfy the heating requirements using a water heater. This can reduce first-costs considerably.
Provide task lighting.
By minimizing ambient lighting in commercial spaces and providing task lighting, significant energy savings for lighting and cooling can often be achieved even while first-costs are reduced.
Minimize outdoor lighting.
Eliminating or reducing outdoor lighting (including through use of motion sensor controls) will both save energy and reduce light pollution, while saving money. Safety concerns can be addressed by designing the outdoor spaces and landscaping with night safety in mind.
Use salvaged materials. Salvaged materials can often - but not always - be obtained at lower prices than new (virgin) materials. Salvaged materials are beneficial environmentally because their use saves natural resources and reduces pressure on landfills. Examples of salvaged materials we can use include lumber, millwork, certain plumbing fixtures, and hardware. Make sure salvaged materials are safe (test for lead paint, asbestos, and other contaminants). Also, don't sacrifice energy efficiency by reusing old windows on exterior walls, and don't sacrifice water efficiency by reusing old toilets, showerheads, or faucet aerators. Finally, be aware that higher labor costs might be associated with use of salvaged materials.
Use structural materials as finish materials.
Whenever we can use structural building materials as finish materials, we eliminate a building component that is costly both in resources and dollars. Examples include exposed beams, concrete floor slabs, and tilt-up concrete panels. It may be necessary to spend more on the structural component to satisfy design and aesthetic objectives (e.g., pigmenting and texturing concrete), but those costs are usually far lower than the costs of separate finish materials.
Consider patios instead of wood decks.
For durability, most wood decks are made from pressure-treated wood or from rot-resistant types of wood - the best of which are from old-growth forests that are in limited supply. A lower-cost alternative (in some parts of the country) is to build concrete, stone, or brick patios. Masonry costs are highly variable and may not always be less expensive than decks.
Avoid multiple-pane windows.
Instead of multiple-pane, true-divided-light windows, install windows with large, single panes. These generally offer better energy performance, are more durable, require less maintenance, and cost less. Over a certain size, however, thicker glass requirements will increase costs.
Avoid garbage disposals.
Garbage disposals require significant quantities of water for their operation, and they result in high organic loading of sewage treatment plants or septic tanks. Composting is a much better option for organic wastes. When outdoor composting is not an option, consider worm bins.
Downsize hot-water pipes.
With water-conserving plumbing fixtures, it also makes sense to downsize the supply pipe diameter. These will deliver hot water faster, reduce standby losses from hot-water pipes, and reduce water waste. Smaller-diameter pipes are also less expensive.
Salvage usable materials.
With renovations, salvage materials removed from an existing building for reuse. Generally, the extra cost of doing this can be recovered through sale of the materials, or, through advertising the availability of free materials, it may be possible to save on labor costs by having the salvaged material recipients do the salvaging. In either case, moderate savings (depending on local tipping fees) can often be achieved through avoided disposal.
Recycle construction waste.
Carry out a comprehensive job-site waste recycling program. Some construction waste materials can be sold, thus recovering the investment in separation and separate storage. More significant savings are often achieved through avoided landfilling expense. In large commercial projects, the savings can be dramatic.
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Written by: Environmental Building News
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