Architecture, Engineering & Planning EVstudio | Denver & Evergreen Architect | Colorado & Central Texas | Blog » Commercial

Stair Construction Tolerance and Dimensional Uniformity

Sean O'Hara — Thu, 19 Jan 2012 21:00:50 +0000

The 2006 International Building Code calls out the tolerance for how consistent each stair tread and riser needs to be in a set of stairs. The code refers to it as dimensional uniformity. What the IBC states on stair tolerance is that the difference between the largest and smallest riser height and the largest and smallest tread depth can't be greater than 3/8" within a flight of stairs.

With spiral stairs the 3/8" is measured at the 12" walk line.

Originally posted 2011-05-24 00:36:39.

The Easiest Place to Find Fire Rated Assemblies is the Gypsum Association Manual

Sean O'Hara — Thu, 19 Jan 2012 21:00:47 +0000

After several projects of fighting with the UL Manual (Underwriters Laboratories) and the International Building Code I discovered that there is a much easier visual way to find fire rated assemblies.

I use the Gypsum Association Fire Resistance Design Manual. Everything is visual and it is generally acceptable to building departments. It contains the most used gypsum fire rated designs and it also contains information on sound ratings for most of the assemblies. Plus it is a free download which the others are not.

The main note is that you need to read the ratings carefully where some of them are proprietary and designed for one manufacturer's gypsum product. In many cases there will be another number for the same assembly from a different manufacturer or a generic product. You can list them as alternates.

In addition you should read the general notes at the front, they tell you about ways that you can modify the assemblies and still maintain something acceptable for the rating. This is important for adding insulation, adding other layers to the assembly or changing the size of framing members.

Finally, if you need a rating that doesn't involve gypsum board then your best bet is probably Chapter 7 of the IBC. That's where I go for concrete and other assembly materials.

Originally posted 2008-10-27 22:27:18.

Accessible and Smart Rec Center Cabana Design

Matt Svoboda — Thu, 19 Jan 2012 21:00:45 +0000

One of the most important functions of recreation center cabanas in family locker rooms is providing a convenient place for users of all physical ability levels to change in comfort and privacy. As the recreation center cabana concept has become more common, the diversity of target users has increased and the types and arrangements of fixtures has evolved as well. Cabanas now are often larger and better designed to not only accommodate wheelchair users but families and seniors also. Standard clearances and adjacencies are of course observed, but there are other factors for an architect to consider:

The Bench - An accessible bench is required by code for the rec center cabana to be considered a changing room or part of a locker room, and benches of this kind are often misinterpreted. The bench is required to be 20-24 inches deep and 42 inches long minimum, and is required to allow a parallel approach on a SHORT end of the bench. This means that a wheelchair user should be able to position themselves with their back to the wall and slide onto the bench in a manner similar to how they would move onto the retractable seat in a shower. Also, consider using a longer bench (up to 6 feet) if you have the room. Not all of your disabled guests need a wheelchair! For your guests which need assistance getting dressed, a place to lie down fully can be a big help. If you are concerned about using up too much space, make one "deluxe" room and minimize the rest...your users will remember which one it is!

Door swing - Swinging a door out of a room is a common trick when having trouble with required clearances in the room, but in a high-traffic area like a family locker room it is often inadvisable to allow a door to swing out for fear of hitting someone. Try keeping all plumbing fixtures on the wall opposite the cabana door to allow the maximum door maneuverability.

Toilet partition - The biggest eater of space in any accessible area is the turning radius. This can be exacerbated by the desire to have an individual toilet partition in your cabana which allows one family member (a child, for example) to use the toilet with privacy while others use the shower or wash their hands. If you have several cabanas and space is tight, consider using the toilet partition in only the non-accessible rooms, and you'll find there is greater flexibility and convenience for your disabled users, who frequently use the room solo.

Originally posted 2010-02-26 00:01:04.

Rating of Floors and Ceilings of Exit Enclosures

Bill Foster — Thu, 19 Jan 2012 21:00:40 +0000

(Disclaimer: Code Analysis especially for egress and fire ratings is very building specific and a solution that works for one building may not work for another.)

In a recent project I set about to solve a question that occurs quite frequently in multi-story buildings.

Can you rate the ceiling or “lid” of a stair or elevator enclosure thus avoiding the expense and complication of taking the rated walls to the bottom of the roof? What I found is still somewhat inconclusive. On this building the IBC allows for a rated lid as long as it matches the rating of the vertical walls (IBC 2009, Section 708.12).

The only problem is that ceiling assemblies do not have their own ratings. Only Floor/Ceiling or Roof/Ceiling assemblies are given ratings. This can be handled by making the ceiling of the vertical enclosure into a Floor/Ceiling assembly. If you are dealing with a building type that allows for combustible materials such as plywood in your floors then there are relatively simple assemblies that will work.

If not then the assemblies get more expensive and it may be in your best interest to take the walls of your enclosure to the bottom of the roof deck. This was the case in this building.

That choice brought up another question:

Does the roof have to be rated at the top of a stair or elevator shaft?

The answer on this particular building appears to be no because the IBC only talks about the walls of vertical enclosures being rated and does not mention the top and bottom.

IBC 707.3.2 “fire barrier separating building areas from an exit shall exit shall comply with Section 1022.1.”

And

IBC 707.5 “Continuity: Fire barriers shall extend from the top of the floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above and shall be securely attached thereto.”

Based on these sections I concluded that for this particular building taking the exit enclosure walls from foundation to roof deck was the most straightforward approach and that neither the floor or the roof needed to be rated.

Originally posted 2010-12-06 00:27:00.

The ADA, ICC/ANSI A117.1 and Kitchen Sinks in Break Rooms

Anthony Ries — Thu, 19 Jan 2012 21:00:38 +0000

Building codes and guidelines are always full of exceptions and variations on a theme and the Americans with Disabilities Act is no different. The ADA was first created in 1990. It is designed to protect against discrimination based on disability. The act has five titles or sections. Architects deal primarily with Title III – Public Accommodations. Since passage the ADA guidelines have incorporated information from the model building codes such as the IBC in order to reconcile differences.

Kitchen Sinks

In a typical situation an accessible kitchen sink has to have a clear space beneath. This allows a person in a wheelchair to approach the sink and get close enough to effectively use it. Generally, this requires such a person to get their knees under the sink while still having a clear area for their toes.

Most office break rooms consist of countertop and cabinet space, a refrigerator, coffee maker and a toaster oven. In this situation a parallel approach is allowed at the sink. This allows there to be a standard base cabinet under the sink.

What is the difference between a break room and a typical kitchen? Cooktops and ranges. In a space with a kitchen sink but no cooktop or conventional range, a parallel approach is allowed to the sink by section 606.2, exception 1 of the ADA guidelines. It is also important to know that countertops in such spaces must be no higher than 34” and no deeper than 24”

Originally posted 2010-12-02 00:06:19.

Green Roofs – Drawbacks and Benefits

Anthony Ries — Thu, 19 Jan 2012 21:00:22 +0000

Green roofs are a fairly new occurrence in the United States. Chicago and Portland are the two cities that have the highest number of green roofs. There are a few disadvantages that can be reasonably offset by careful planning and the inherent benefits to green roofs. Careful consideration should be given before moving forward as site selection and climate can have a large impact on the success of a green roof. Read on for a quick discussion of the more common disadvantages and advantages.

Disadvantages:

Increased installation costs – often double that of a more conventional roof

Increased maintenance costs –potential water, weeding etc. required

Increased structural requirements – can vary greatly by type of green roof

Difficult to service roof if needed – extensive roof are more easily serviced

Advantages:

Storm Water Management – Green roofs help reduce the amount of water that runs off a roof and into municipal storm water and sewage treatment systems. Intensive systems are the best at this due to the deeper growing medium. This also acts as a first step in water purification. The vegetation and growing medium will trap contaminants from rainwater.

Heat Island Effect – If you have ever stepped from an asphalt parking lot onto grass and felt the difference in temperature, you know what the heat island effect is. Green roofs can substantially reduce the ambient temperature on the roof of a building and that contributes to overall cooling a local climate.

Help filter pollutants from air – As briefly touched on above, green roofs can help filter contaminants from the air. Studies have shown that green roofs can remove as much as 95% of heavy metals from the atmosphere.

Increased lifespan of roof – We have all seen what the sun can do to our BBQ grille covers and car paint over the years. Since the green roof covers much, if not all, of a conventional roof, that roof is going to last much longer. Some studies have shown up to 3 times longer. Most properly installed commercial roofs have a 30 year warranty.

Regulates interior temperatures – By reducing the heat island effect the green roof is also reducing how much heat there is to move through the roof. This combines with the great mass and creates a roof that is insulated quite well in both the summer and winter. The amount depends on the thickness of the growing media and its’ water saturation.

Aesthetic and Use Benefits – A green roof is a more attractive roof. Think of how much potentially usable space is wasted just covering the building. Imagine incorporating outdoor spaces for use by the building tenants. For some extra cost a building owner gets more usable space that can be a very attractive selling point to potential tenants.

Ecological Benefits - Green roofs can attract birds, butterflies and bees. Some buildings are known to harbor large bee farms creating another potential revenue stream for the building owner.

There are other considerations with green roofs but this covers the most common and influential. When choosing any building method or component it is important to analyze how the advantages and disadvantages compare.

Originally posted 2010-12-08 00:30:18.

Why Hire an Architect When a Contractor Offers to Design-Build

Sean O'Hara — Thu, 19 Jan 2012 21:00:15 +0000

Design-build is a common delivery method in construction and a popular buzz word in the industry. What it generally means is that you hire a single person or company who both designs your project and builds your project. Design-build can be great and it can be a real mistake. What is important is to know who the players are behind the design-build label.

Just to admit bias to new readers, EVstudio is an architecture and engineering company, we participate in many projects titled "design-build".

Design-build can be a great setup where you have a company that has experts and licensed professionals working on both the architecture and construction portions of the project. They can typically deliver a project on budget and they may be able to reduce your upfront design fees because they bury them in your total project cost.

Unfortunately, what often happens is that the design-build team is an outgrowth of only one profession. You frequently have a general contractor who has decided that they can do the design work as well. Suddenly you are hiring someone to design your home who is only marginally qualified and yet you are paying enough for the service to hire a full time architect. With this approach you are also hiring someone to design the project who is often most concerned about the simplest details and is likely to give you reasons that you can't have something more complex.

What I would advise all clients entering a design-build setup to do is make sure that you know who is actually doing the designing on the project. You should be meeting with the architect directly and be pleased with the design work that you are receiving. When we participate in design-build we meet with clients directly for the design and the contractor meets directly for the build. They only pay one bill but it is distributed according to the work involved. The architect is your advocate and more able to provide solutions based on years of full time design experience rather than excuses.

Another solution that works well for the client is hiring an architect and a contractor at the same time and working as a team throughout the project. We do this with many of our favorite contractors and it is a rewarding way to bring experienced professionals and still give the client an integrated project. While it is not truly design-build it offers many of the advantages.

There are a large number of project delivery methods in architecture and construction, please ask questions or give us a call.

Originally posted 2010-01-20 00:01:06.

Finding and Choosing the Best Architect for Your Project

Sean O'Hara — Thu, 19 Jan 2012 21:00:01 +0000

Last week I gave a talk on "How to Work With an Architect" as part of Colorado Architecture Month. One of the questions from the audience was "how do I find the right architect for my project". Of course I told them to just talk to me afterward, but it did raise an interesting question. How does someone go about finding an architect?

Your first option is always referrals from other friends and family members that have worked with an architect. If you have already selected a builder or contractor for your project they may have some recommendations based on their experience.

Oftentimes, the next source should be the local chapter of the American Institute of Architects (AIA). Both the national website and the local websites have tools to link you to architects that do the type of project you have in mind. Not every architect is a member of the AIA, but I'd recommend working with an AIA architect.

The next source is going to be the internet. My main caution is that you'll really want to dig through the results. In my test searches, many of the top page results are about architecture but not necessarily about architecture firms. In addition, the top search results are often about larger firms who may not be the right choice if you have a smaller project.

The phone book is an option, but without any images of the work, it could make for a daunting task.

Finally, one last plug for my company, EVstudio. We do a wide variety of project types and a variety of styles throughout the country. Please feel free to email me or give me a call. I'm happy to give you advice on your project and if I can't help you, I'll give you good advice on your architect selection.

Originally posted 2009-04-19 23:34:37.

Don't Make Your Solid Blocking Too Solid – Attic Ventilation Requirements

Sean O'Hara — Thu, 19 Jan 2012 21:00:00 +0000

I was at a job site today and noticed that the contractor had used blocking between trusses where the blocking was large enough that it actually blocked off the ventilation from the soffits. They're going to have to go back and put holes in the blocking to meet the ventilation requirements.

Therefore it seems like a good time to review the ventilation requirements in the International Building Code.

First off, you need at least 1" of airspace between the insulation and the roof sheathing. The venting must have a total area of at least 1/150 of the ventilated area and at least half that area must be in the upper portion located at least 3' above the cornice or eave vents. So where you have a 3,000 sf attic you'd need 20 sf of venting with at least 10 sf of that in the upper portion of the roof.

The International Residential Code states that no more than 80% of your venting can be in the upper portion of the roof, the IBC does not have this requirement.

Where you have a vapor retarder with a transmission rate less than 1 perm on the warm side of the insulation you can reduce the venting area requirements by 50% to 1/300.

Finally remember that openings for ventilation need to be covered with material that has a minimum 1/8" openings and a maximum 1/4" openings.

Originally posted 2008-12-30 22:31:45.

Implementation Date for 2010 ADA Standards

Sean O'Hara — Thu, 19 Jan 2012 20:59:58 +0000

We've begun to see the 2010 ADA (American's with Disabilities Act) Standards brought up on new construction projects. Like many codes the date in the title is not necessarily the date where it begins to apply. Given that commercial projects tend to takes month and sometimes years to construct, the long lead times help.

For the 2010 Standards the code applies to any projects where the start date of construction is on or after March 15, 2012. Before that date the 1991 Standards without the elevator exemption , the UFAS or the 2010 Standards can be used where the start of construction commences on or after September 15, 2010.

If projects can't start construction with a month or more of leeway, its advisable to go ahead and start using the 2010 ADA.

Originally posted 2011-08-17 00:58:17.