Sunday, December 29, 2013

Hoboken Brownstone- HVAC

You may have seen one of our projects in the last issue of Hudson Mod...

Photography by Elliott Kaufman

and it happens to be the same project that we've been writing about on the blog.  We hope this series gives 'would be renovators' a peek into what's involved in this type of brownstone construction project.  We've gotten lots of positive feedback on how helpful the series has been, so I'm determined to wrap it up!

We had left off with HVAC (Heating, Ventilating and Air Conditioning).  It can be a dry subject but a very important one during the design process to understand how the system will feel, function, and be integrated into the design so it's a hidden comfort.   

In this project, we had a combination of systems to produce the heat, with radiant floors on the Basement and First Floor and forced air at the upper floors. Radiant  floors offer a very comfortable heat but it is a more expensive system to install.  Air conditioning  was distributed through the forced air system on all floors with air handlers at the basement and top floor.  

Forced air ductwork can be sizable so it needs to be planned for early in the design so you don't end up with soffits and chases in obvious places. Here's a soffit that we had planned for in the basement... 

Framing & Ductwork at Playroom

We knew this would be a cabinetry wall so it ended up being concealed within the walnut woodwork with registers to match.  The wood clad soffit ends up being flush with the doors so it disappears into the cabinetry. 

Finished Basement Playroom

At the upper floors, the rooms at the center of the house have slightly lower ceilings where we have the bathrooms, closets and utility spaces.  The ductwork is located above those ceilings with sidewall registers into the front and back rooms to maximize the height of the important spaces.  Here you can see a register in the upper left hand corner into the Master Bedroom.  The ductwork runs over what will be the Master Bathroom...

Master Bedroom Framing

Here you see the high register in the finished space... 

Master Bedroom looking into Master Bathroom

Another trick we used to get ducts to the middle floor without soffits was using an oval duct down the front and back walls of the brownstone. You can see the oval duct centered between the windows here... 

Top Floor rear wall

It then terminates as a ceiling register in Master Bedroom above the bay window...  

Master Bedroom Bay Window

We also used floor registers for the AC distribution at the First Floor. This works well at the Kitchen where there will be heat gain in the summer from the large window unit...

Photography by Elliott Kaufman

In a previous post, we showed the basement mechanical room which houses one of the air handlers.  We also put one at  the top floor in a mechanical closet to feed the upper floors.  You can put them in the attic but we wanted to keep the ceilings high so we had limited clearance. This location also give easier access to the unit. Here you can see the large round  return duct coming down into what will be the mechanical closet... 

Top Floor Framing & HVAC

Because we planned to make the house air tight, we needed to incorporate a ventilation system called an ERV (Energy Recovery Ventilator).  This air exchange unit provides fresh air into the house 24/7 without loosing your heat.  The heat from the air exhausted is captured and put back into the fresh air coming in. Each floor has returns in the bathroom and kitchen type spaces and supplies in the living and bedroom spaces.  The ducts are small and easy to route within the floors joist.  Here's one that hasn't been anchored in the joist bay yet...

ERV Ducting

I'll talk more about this system in a future post as it relates to our own Passive house where a ventilation system is required because the envelope is sealed so well.  You can see our unit here with the main unit at the bottom and the tubes coming out of a silencer box and tubes coming into a manifold.   The small light rectangle on the main unit is the filter that gets pulled out and replaced.

ERV system

Even if you don't live in a house as tight as these, the system is still beneficial in that you are receiving constant filtered fresh air without heat loss. Great for those with indoor and outdoor allergies!

We maintained the existing fireplace locations in the Living Room and Master Bedroom, but needed to install all new flues within the existing masonry chimneys to allow for new gas units.  We cleaned up an existing mantel for the master bedroom but installed all new mantel trim and tile surround at the Living Room seen here...

Photography by Elliott Kaufman

This is just one system setup that was catered to a particular client's budget and needs. There are many other system options that should be reviewed carefully to get the right fit for a specific project.  Often we judge the value of a property based on its aesthetics and visual appeal, but the thermal comfort of your house has the ability to make it feel like a home.