If you’re renovating a historic building in New York City, the HVAC solutions you choose can be a very important decision. It may not be the first thing on your mind, compared to structural and design decisions. However, choosing the right HVAC systems and installers means you get the comfort conditions needed for the intended use of the space, while also doing a good job with historic building preservation and maintaining the character of the building.
First of all, when taking on a renovation of a historic building, it’s essential that you consult with HVAC experts who have experience working with historic buildings. That’s because there is quite a lot of damage that can be done when installers don’t understand the specific requirements of older buildings. It’s also important to realize that each historic space is unique and needs to be properly evaluated to select the right HVAC solutions and installation options.
There’s a great deal to know about what to do and not to do when selecting, installing and even maintaining HVAC solutions for historic buildings.
Today we’re sharing the first in a two-part series about the DOs and DON’Ts you should be aware of when making decisions about HVAC solutions.
Let’s start with the DOs.
HVAC solutions: 9 DOs for historic building preservation
1. DO understand the new usage of the space
This is something that is frequently neglected when a historic space is renovated for commercial use before a new tenant has been selected for the space.
It’s understandable for a building owner to want to complete renovations to make the space more desirable to prospective tenants. However, HVAC solutions need to be customized according to the usage of the space. For example: a restaurant has vastly different climate control and ventilation requirements than an office space or a boutique. Without understanding usage requirements in advance, you may end up installing HVAC systems that are too large or too small.
In a historic building preservation, the goal is to keep as much of the existing space and finishes as you possibly can. One way to do that is to minimize the size and complexity of AC systems by adding shutters, awnings, operable windows and ceiling fans (or keeping existing ones intact) to reduce cooling loads.
3. DO add insulation: the right way
Adding insulation and vapor barriers is a great strategy to improve energy efficiency, as well as reducing both heating and cooling loads. However, adding insulation to walls in a historic building preservation can be tricky without damaging interior wall finishes or exterior cladding or stonework. Best practice can be adding insulation in basements and attics in those cases.
4. DO consider the weight of the equipment
Remember that the structural systems of historic buildings were not designed to bear the weight of modern HVAC equipment. When this additional weight is not planned for in the selection and placement of equipment (along with the vibrations the equipment can produce), structures can be weakened or damaged.
5. DO factor in ceiling heights of older spaces
When designing distribution systems and placement of HVAC equipment, be aware of the potential impact on ceiling heights. Some historic buildings may have low ceilings that make it impossible to add ductwork or air handlers. Or you may have the opposite situation: beautiful high ceilings that you want to preserve. In either case, take advantage of existing shafts, chases and even closet space for air distribution systems when the ceiling is not an option.
6. DO minimize impact of HVAC solutions on architecture and finishes
Of course you want to keep gorgeous high ceilings in your historic building preservation project. And you also want to retain historic finishes like moldings, plaster walls, woodwork, stonework and even decorative elements like wallpaper and switch plates. When choosing HVAC solutions and design, minimize changes to these elements as much as possible.
7. DO reuse existing HVAC elements when possible
Those old grille covers and radiators can be beautiful, and something that should be built into the new HVAC solutions whenever possible. For example, you may be able to keep existing radiators while adding a new boiler and updating the distribution.
If the ventilation is still usable (or it’s possible to update without redesigning the placement), then you may be able to keep the ornate grille covers, while adding more modern controls. If you can’t use existing grilles, at least add less intrusive ones such as slot registers.
8. DO plan for humidity control
Proper humidity control is essential for historic building preservation in order to prevent deterioration of the historic building materials such as woodwork, masonry, plaster, and even fabrics. In some cases, humidification may be needed in the winter and de-humidification in the summer.
Related article: HVAC Humidity Control: 5 Reasons Your AC Is Ineffective
9. DO provide access to equipment for HVAC maintenance
Especially in a historic building, it’s smart to plan in advance for regular preventative maintenance on the new HVAC solutions. Even new equipment needs regular cleanings, inspections and tune-ups to keep it operating efficiently and effectively.
Here’s something else you may not realize: preventative maintenance actually saves you money by preventing breakdowns and large, unexpected repair bills. Regularly cleaning coils, replacing worn parts and checking wiring can prevent small problems from turning into big, expensive ones. Here’s an example: dirty coils, or poorly operating fans force your system to work harder, which can lead to compressor failure (and often a death sentence for your AC unit).
So that’s why it’s smart to plan for HVAC maintenance during your historic building preservation project, by providing easy access to equipment.
Related topic: Q&A about HVAC Preventive Maintenance Contracts
NEXT TIME: We’ll continue our series on HVAC solutions for historic building preservation, by exploring the DON’Ts you need to know as well. DON’T miss it!