Category Archives: Code

Water Heater… Fail

New water heater

New water heater

Almost everybody has a water heater story. I have four. Here’s my latest.

Just days before Christmas, there was a familiar pool under the water heater stand in the garage. It was hard to accept because I was pretty sure we had replaced it not very long ago. A little research in the file showed it had been replaced exactly six years and one day earlier. Of course, the warranty on the unit was… six years.

Apparently, recent Federal energy efficiency requirements mean that tanks have thinner metal than ever before. This reduced thickness ensures heat from the gas burner below is more quickly transferred into the tank and reduces the amount of total energy required to heat it. It also means that the tank will rust out faster. In my case, exactly as long as the manufacturer predicted.

There has been a lot of talk recently about tankless water heaters. They used to be called instantaneous heaters, but tankless seems to imply a reduced risk of exactly the kind of failure I had. There are more pros and cons.

First, tankless water heaters have been around a long time. Electric coffee brewers are essentially the same technology. Water is heated in small quantities as it is needed. The unit is sized to blast heat into water passing through a pipe as it flows. Instead of a coffee, they are scaled up for a home, adequate for a shower, clothes washer, or bath tub. This requires a tremendous amount of energy for just a few minutes, although theoretically cheaper than heating 40 gallons of water continuously day and night.

It is true that the energy savings is considerable. The trade-off is that the equipment and the utility service must be increased to manage the short bursts of gas or electrical energy required to heat the water so quickly. Current whole-home tankless heaters have 25 year warranties. These are mostly new models without testing long enough to prove it. Economically speaking, long warranties indicate untested or unreliable performance, from cars to electronics to water heaters. Incidentally, there are also fiberglass tanks with “lifetime” warranties that have been on the market for five years.

Water heater controls

Water heater controls

In our area, a lot of existing homes have gas tank water heaters. In the region’s building boom twenty years ago, gas was cheap and burning fossil fuels wasn’t considered as taboo as today. Electricity is now popular again because it is relatively more competitive. It is also more flexible across the many types of potential utility energy generating methods like coal, hydroelectric, and photovoltaic. However, converting a gas tank water heater to an electric tankless one requires an enormous (and expensive) electrical circuit to be added. Some homes don’t even have the electrical service to handle it.

To work around this limitation in retrofitting an electrical tankless heater, there are gas models. These still require electricity to ignite the fuels, but the circuit is small and reasonable. So the implementation becomes more feasible. But there is still one major drawback as I see it.

The great blizzard of January 2014

The great blizzard of January 2014

The most significant issue with instantaneous water heating is that if the utility service goes out for even a minute, the unit ceases to operate until the utility is restored. The best benefit of a tank is that momentary blips and even short outages don’t impact hot water availability. Even better with gas is that it remains functional throughout electrical power outages. Although we rarely have ice storms, the few memorable ones are enough to second guess depending on electrical utility power for hot water.

Another issue is cost. Tankless heaters are 50-100% more expensive. I got a good quote to replace my hot water heater at $1,800. The tankless gas heater would have been $2,700. Electrical tankless wasn’t even an option, my panel is simply not large enough.

Payback

Payback

For a new house, the equation is a bit different. Since the electrical service, panel, and circuiting can be properly sized from the outset, upfront costs are a much lower barrier to installing a tankless heater new. While it is important to size the unit to handle the expected hot water load for the likely extremes (such as multiple teenager showers and laundry loads), monthly energy savings may pay back in only a few years.

One final consideration is the actual configuration of the unit. My water heater failures have been restricted to the garage. But it is common in this area to find them located in attics over living spaces with poorly installed containing pans that create catastrophic water damage when they fail. A tankless type can reduce the size of the failure and can also save some space in the garage or attic since they are several times smaller.

I was fortunate that my water heater’s manufacturer decided to replace my water heater under warranty. It covered the cost of the unit even though I still had to pay $600 for the labor. For a repair, payback alone is unlikely to justify replacing a tank type with a tankless. However, instantaneous water heater disadvantages may be outweighed in new homes or in repairs by homeowners with environmental, energy saving, risk managing, and space making interests.


Code Check

Back of House

Back of House

I often receive inquiries about providing permit drawings requested by local authorities for new tenants, small renovations and upfits. Business owners are moving into a new space and the local Authority Having Jurisdiction (AHJ) has required permit drawings sealed by an architect to gain legal occupancy. This can be a relatively simple process. But it can also be complicated by only a detail or two. Here are some of the more typical complicating factors.

Existing Information

Permit drawings are almost always required to be scaled. Architects produce documents that are special in many ways, but one of the most important is that they represent three dimensional space in both measurement and proportion. This enables the drawings to accurately reflect required dimensions such as distances to a fire exit, clearances, area sizes, quantities of materials, and so on.

When a space is already existing, such as in a shopping center or office tenant space, it is important that this existing facility information be presented as part of the permit submittal. Sometimes a landlord already has CAD information of the building and site, which saves time. But when this existing information is less than what the AHJ will require, the architect and his consultants need to conduct a field survey to obtain the outstanding information.

Gas meter

Gas service and meter

These drawing components include typical items required on the average building permit set.

Building Code Summary — This is usually near the front of a set of documents and is a large listing of the building code requirements and existing building measurements used to explain the original or most recent building permit for the property. It prescribes the basic building construction type, occupancy classifications and uses, information about fire partitions and barriers, emergency exiting plans, and much more.

Suite Layout — Where multiple tenants are in a building, many jurisdictions require a layout of all the suites in the building.

Site Plan — A site plan shows property lines, surrounding streets, drives onto the property, all parking spaces including accessible ones, walks, plantings and natural areas, fire hydrants and sprinkler connections, and the building, its entry and exits. Where multiple buildings exist on the property, clearances between buildings must be known.

Structural Drawings — These are often needed when new equipment is being added or changed above the ground floor or on the roof. They also explain where major structural components of the building are being adapted, such as with wall openings, wall-mounted equipment, or significant ceiling suspended items.

Architectural Floor Plan — This plan shows all the spaces in the building, including areas outside those of the intended project. Particularly of interest are the corridors, stairs, exit door configurations, and fire extinguisher cabinets. The architectural floor plan needs to correctly indicate all walls, doors, windows, stairs, and elevators at the correct sizes. It also includes furniture, fixtures, and equipment that are intended in the final space, including toilets, sinks, bathroom partitions, cabinetry and casework. Any other floor-mounted trade items in the sections below are often shown on the architectural floor plan as well.

Reflected Ceiling Plan — This is a drawing necessary to show the general ceiling configuration and height, lighting, exit lighting, exit signs, HVAC grilles, fire sprinkler heads, smoke detection, and alarm horns and strobes.

Building Elevations — For an interior space, this seems an odd necessity but some AHJs (like Raleigh and Cary) are very particular about hiding rooftop HVAC systems and want to see all the views of the building exterior. A roof plan might also provide this information.

Roof Plan — This plan is be necessary if HVAC or other systems have rooftop work in the project.

Fire Protection — Usually only for sprinklered buildings, these include sprinkler piping, sprinkler heads, calculations, and the valves, connections, and supporting equipment.

Plumbing — In addition to piping, plumbing drawings show fixtures like toilets, sinks, lavatories, and janitor sinks. Also explained are water meters, backflow preventers, building water and sewer connections, and the calculations supporting the design.

Mechanical — In addition to any HVAC units and related ductwork, mechanical drawings show important information regarding calculations for air changes, humidity control, ventilation provisions, and many other details related to the mechanical design of the building.

Electrical — These drawings indicate electrical power service and distribution, lighting and controls, services to mechanical systems, and all the incidental components requiring power such as appliances, equipment, and fans. The electrical drawings often include critical fire alarm systems as well as those for data of internal and external networks, phone systems, security, intercom, and even audio-visual.

These and plenty of other items could require illustration by the local authorities during permit plan review.

Change of Use

Although it doesn’t always require large changes in the building, modifying a space from one use to another can trigger further requirements or changes. By code, the use includes both the occupancy classification (Business, Assembly, Retail, Industrial, etc.) as well as the particular function within the spaces (warehouse to auto repair, accountant office to medical office, office space to retail space, etc.) The building code has particulars about many different functions so it isn’t possible to generalize about how these could develop. I like to research these at the beginning and even discuss potential conflicts with the local authority early in the process to avoid surprises during the final inspection.

Push bar

Push bar exit device

Code Changes

Even without changing occupancy or use, the building code itself is continually adjusting in reaction to scientific, political, and cultural interests. Officially this happens every two to four years, but subtle clarifications, amendments, or local adjustments can happen any time. Just because a space was compliant five years prior doesn’t mean it satisfies current requirements. And AHJs use new tenant occupancies and renovations to review existing buildings to reflect increasing concerns for fire safety, accessibility, plumbing fixture counts, and general life safety.

Renovations, Up-fits, and Changes

Each AHJ has slightly different stipulations for just how small an alteration can be before it requires a building permit. But it is safe to assume that only a few inches adjustment to the direction, width, or configuration of a path of travel in a room, along a corridor, through any door, around an object, or across the site to the public way will require a permit submitted with architectural drawings.

This process sometimes seems picky, even to this architect. But its primary purpose is to “safeguard the public’s health, safety and welfare”, in the words of the state statute by which architects are licensed. Since even the AHJ is not licensed, the building code review process basically pins responsibility on the architect to ensure compliance. The requirement for sealed drawings is the legal method for accomplishing this.