Sunday, February 26, 2012

Planning a Phased School Renovation and Expansion

School renovation and expansion projects are commonly related to overcrowding and/or obsolete facilities. Construction in phases may be the only choice when school operations must continue in the same building or on the same site during renovations and expansion. Phasing needs and requirements should be considered during the design of such a project in order to ensure that provisions are adequate for ongoing school operations during each phase of the project.
Phasing plans and specifications should be based on at least the following considerations:
1. Each phase should provide sufficient classroom space for the enrollment. It may be necessary or advisable to rent or purchase relocatable modular classroom units for use during one or more phases of the project. The actual determination of necessary classroom count should be made by the school authority.
2. Construction areas must be adequately separated from occupied areas.
a. Separation walls may include a combination of existing walls or partitions and temporary or permanent new construction that affords the required fire separation and minimizes dust, fumes, and noise transfer from construction areas to occupied areas[1]. It also, of course, must adequately separate construction personnel from building occupants.
b. Construction fencing should be planned to separate contractor staging and construction areas from owner/user areas, neighboring properties, and public areas (e.g., streets and sidewalks). The fencing layout may need to change from phase to phase.
3. Utilities should be adequate and uninterrupted[2] in the occupied areas of the building. These utilities would typically include heat, lights, power (normal and emergency systems), telecommunications, water, sewer, fire protection and alarm systems.
a. Replacing boilers in a school can take as long as six months, especially if hazardous materials removal is part of the process, so the heating season should be considered when determining project phasing and the feasibility of replacing a heating plant in the existing location. It may be more practical to construct a new boiler room in order to minimize downtime and the risk of delays.
b. In order to maintain existing electrical services, it may be necessary to build a new electrical service entrance and backfeed the existing systems that will continue to serve existing occupied areas[3]. These backfeeds may be different for each phase of a project.
c. Any of the utilities may need temporary connections, extensions, routes, “jumpers”, supports, and/or temporary equipment in order to satisfy the need for adequate and uninterrupted utilities in occupied areas[4].
4. Adequate exits (i.e., egress facilities) must be provided. Exits must be adequate in width and arrangement to meet applicable code requirements. Exit calculations should be performed to determine code compliance. If any existing exits will be blocked by a phase of construction, the remaining exits must be sufficient in arrangement and width to meet code requirements[5], or additional permanent or temporary exits must be provided. Exit signage and lighting must also be coordinated with the exit arrangement for a given phase. Temporary[6] corridors may be necessary to link occupied parts of a building that are separated by construction areas. Protected exit walkways may be necessary to link building exits to the public way and maintain separation from construction areas.
5. Toilet facilities must be adequate to serve the occupied areas of the building. In some cases, this may influence the delineation of phases or the location of new toilets.
6. The need for food service must be addressed throughout phased school construction. Food preparation, service, and dining areas may need to be relocated to accommodate renovation and/or new construction. The challenge is reduced if food is typically prepared in a remote facility and delivered to the school undergoing renovation, but the challenge may be greater if the school undergoing renovation houses the main kitchen for several schools in a district. Can a temporary source or provider be arranged to prepare and deliver adequate meals? And, if the cafeteria itself must be offline for renovation, can an alternative space be used?
7. Athletic facilities use tends to vary seasonally. It may be practical to take a gymnasium offline during the months when physical education and other athletic programs can be accommodated outside. This consideration may influence the phasing schedule such that gymnasium renovations occur during warmer months; and field improvements may need to be completed during summer vacations or planned such that new fields are completed before existing fields are improved or taken offline.
8. Parking must be maintained or provided in sufficient quantity and condition to serve the building occupants. The parking arrangement may need to be changed from phase to phase to satisfy the requirement. Walkways must be included to connect parking areas to building entrances. Parking areas for building users should be separate from construction parking areas.
9. Separate driveways should be planned for building users, school buses, and construction. The typically desirable separation of school buses from cars should be part of each phase, and a separate vehicle entrance to the site should be planned for construction personnel and deliveries.
10. Air intakes must be protected from dust and fumes. Temporary air intake “stacks” may be necessary at building air intakes adjacent to construction areas to avoid contaminants related to construction.
11. Accessibility features that are required for the school facilities must be maintained as part of each phase[7]. These would include, for example, ramps and elevators to the extent required.
Timely phasing considerations are likely to influence a project design in ways that will make construction less disruptive for building occupants.
The requirements related to phased construction should be clearly established on the drawings and in the specifications that will be used for bidding and constructing the project.



[1] Special requirements applicable to hazardous material removal may be more stringent and take precedence over general criteria based on desirable separation. Also, the EPA has published indoor air quality (IAQ) guidelines for school renovation (see http://www.epa.gov/iaq/schooldesign/renovation.html), and states and other authorities have established similar criteria.
[2] Contract documents may provide for necessary, brief or momentary interruptions to occur during power switchovers and similar changes. If they are necessary during occupied hours, they should be scheduled in advance with the building owner.
[3] Local fire authorities typically want to limit electrical services to a single location where power to an entire facility can be shut off in order, at least in part, to minimize risk to fire fighters.
[4] Special attention is warranted where partial building demolition will sever the services or structural support of services between occupied building areas. The bid documents should be clear in requiring temporary support or temporary rerouting of utilities and/or temporary equipment to serve the remote areas.
[5] The applicable code should be studied to determine whether any reduction in egress capacity is allowed, even in the case where existing exits exceed code requirements.
[6] The applicable code should be studied for requirements and limitations related to “temporary” construction. The duration of such construction may be limited by code to less than the anticipated duration of use during phased construction. For example, Section 108 of the 2009 IBC limits a permit for temporary structures and uses to 180 days; yet some requirements for temporary structures are not less than what is required for permanent construction. Chapter 31 of the 2009 IBC also includes requirements for temporary structures and for special construction that may be considered applicable to temporary facilities for phased school construction.
[7] Accessibility requirements would typically apply also to temporary modular classroom units.

Wednesday, November 23, 2011

A Few Predictors of Building Failure in New Construction

The following suggested predictors of building failure in new construction are based on years of experience tracing building failures to their causes. While the failures may express themselves as discrete detail flaws, underlying causes are often found in contractual decision making, project administration and management, and in conceptual design. The following predictors do not guarantee building failure, but they do indicate a heightened risk of failure.
  1. Building from Schematic Design or other preliminary design documents – Schematic Design Drawings or other preliminary drawings that are prepared in CAD or a related computer program can appear quite precise, so it is possible to mistakenly expect such drawings to be sufficient for construction. Schematic Design Drawings typically lack sufficient detail for construction and may not be well conceived in terms of how materials and building components relate to one another. There is a high risk of building performance problems, including but not limited to building envelope leaks, when Schematic Drawings or other preliminary drawings are used as the basis of construction.
  2. Eliminating or drastically limiting the Architect’s role during construction – If the Architect is dismissed from the construction phase of a project, or if the Architect’s services are reduced below the standard of practice in order to save cost or expedite construction, there is a heightened risk that changes and substitutions will be made without the review and scrutiny of the Architect, who would be expected to consider the compatibility of changes and substitutions with the design intent or even with code requirements and is expected to know more than contractors do about these matters. (Similar problems can occur if the Architect’s construction administration services are delegated to inexperienced staff, who may not have sufficient knowledge about the materials and systems they encounter on the construction site.)
  3. Insufficient consideration of climate and weather – Success of building designs and design features in one climate are not good predictors of success in a different climate. This is true for building envelope designs in different geographic locations, and it is true for interior design features, materials, and details that are mistakenly used in exterior applications where they are inadequate for exposure to weather, including precipitation and exterior variations in temperature. It is also true for moisture sensitive interior materials that are subjected to high humidity related to building use (e.g., a swimming pool environment).
  4. Assuming that the selection of an innovative, energy efficient product or system will, on its own, lead to a durable, energy efficient building – Examples include rot failures related to SIP (structural insulated panel) construction where panel joints were not properly sized and sealed and where OSB facing material was exposed to moisture in the belief (espoused by the panel manufacturer) that OSB was a waterproof material that need not be protected from moisture.

Certainly, there can be other predictors of building failure in new construction, and avoiding the predictors above may not lead to a trouble free building every time. Still, the issues above appear to be common enough to warrant their listing as predictors of building failure.

Tuesday, November 22, 2011

Planning for Concealed Site Conditions

Discovery of concealed site conditions can raise havoc with a project, possibly disrupting the construction schedule and adversely impacting the project budget. Here's a link to an article I wrote a few years ago to share some of my experience with concealed site conditions: Planning for Concealed Site Conditions

Monday, November 21, 2011

Delegating for Architects

Project results are directly related to the effectiveness of project communications. Successful delegation of responsibilities and tasks depends on effective communication. Download "Delegating for Architects" to read more about this.

Thursday, September 29, 2011

Value Engineering

Any discussion of value engineering (V.E.) is likely to produce a rush of criticisms of the process if you work in an architecture or engineering practice. The architects and engineers are likely to recall bad experiences when V.E. was started late, approaching or following the completion of construction documents, at a time when the project schedule did not allow sufficient time to fully consider consequences and implement V.E. changes in a comprehensive and well coordinated manner. They are likely to complain that "V.E. stripped the value out of the project."

A better approach to V.E. is to start it earlier, when material and system decisions are being formulated and before a lot of time is invested in developing applicable details and specifications.

The Whole Building Design Guide (http://www.wbdg.org/resources/value_engineering.php) offers an excellent synopsis of V.E. and a clear picture of the advantages of doing it earlier in the life of a project.