HVAC for your basement. Let's tame this wild beast.
First things first. What the heck does HVAC stand for? The exact definition is Heating, Ventilation and Air Conditioning. I did list HVAC as one of my 8 phases of how to finish a basement but what you're probably wondering is:
- Will it be to hot in my basement in the summer?
- Will it be to cold in winter?
- Will the air in my finished basement smell and feel fresh and clean.
- Will Zack and Kelly eventually get married.
Ok, that last one I just threw in for fun, if you get that reference then you're
old and dorky like me awesome.
What do you need to do to your HVAC before you finish your basement?
- Do I need to expand my HVAC?
- Do I need to run new ducts?
- Can I just throw in some new registers?
- How do I make sure my system will be balanced once I add my basement
- Does my furnace have a large enough "capacity" to "service" my basement.
Don't freak out me now. I know there are a lot of questions. Let'scool down for minute. Take a deep breath. Get into your best Yoga pose and consider the following:
- You may not need any HVAC changes. Yup. I didn't change a single thing and my basement is money comfortable.
- You may just need a solution for heating. Especially if you live in a cold-ass state like Michigan, New York or Canada (an awesome Country, not a state, I know).
- In most cases you can add a solution AFTER your basement is finished. So if your budget it tight - you might be just fine waiting a bit. (this is what I did)
In this section on HVAC, I'm going to outline, in a simple and fun way, 163 hours worth of boring grueling research, Google searching, Youtube video watching, and general calling up of HVAC guys asking them questions about HVAC for your basement.
Yes, you're welcome.
Let's start by answering this question...
Will You Need to "Expand" Your Basement HVAC
If the air in your finished basement will be either to hot, too cold or too stale then you will want to either expand your HVAC or add a separate unit (more on why I recommend adding a separate solution a bit later).
So how do we find that out.
Measure Your Basement's Comfort Levels
One of the simplest ways is to buy a thermometer with a humidity reader and put it down in your basement. Maybe even buy two - one for your living space and one for the storage area or the space that won't have any access to windows.
I highly recommend this little baby here. You can buy it here on Amazon for around $10 bucks, it's a best seller and has 4 stars. Plus, I've personally owned two of them for over a year and they've been fantastic.
Regardless of which brand / model you decide to buy, make sure is has a daily Low / High hold function. You don't want to just sit down in your basement like a creepy serial killer just staring at the thermometer all day.
Ok. So now we're measuring temperature and humidity. What are we looking for?
For me…. I wanted to make sure the high temps stayed below 74 degrees and the low temps above 65 degrees. And humidity between 30% and 40%
Now wait just one second. If you're thinking "65 is way to cold for me" or "74 degrees, holy Christmas, I'll bake in those temps". Hear me out.
Those are the "extremes". On average I'd like to be at 69 or 70. And guess what - with almost not additional HVAC work that's where my basement temps are about 95% of the time.
What's that? You don't have time to wait 12 months to measure your basement temps - keep reading - I have a few samples below.
Consistent, Comfortable Temperatures - Thanks Mother Earth, Your Rock
Here's what's kind of awesome. The earth (the dirt part of it anyway) has a very regular temperature of about 65 degrees, once you get past the first foot or so going down.
This is why you'll often see insulation only on the top half of the wall of a basement. Because the bottom half of the wall doesn't need it. The ground temps that far down are a constant 65-68 degrees.
3 Factors that can dictate if YOUR basement will be comfortable?
1. What Style of Basement Do You Have?
Is your basement mostly below ground? If it is, you're in luck! The temps will be fairly comfortable and consistent.
My basement is a walk-UP. I have a double door exit to the outside then you have to immediately "walk up" stairs. What this really means is - only the door part of that wall is exposed to the hot sun and cold air.
If your basement doesn't have any exits you're in even better shape (in terms of temp control, in other ways that kinda sucks for you).
If your basement is walk - OUT, then guess what, sad face for you. You might need to spend some extra coin to heat and cool it. The reason is that you likely have an entire wall exposed to the elements.
2. Where Do You Live?
You need to take into account where you live. Me, I live in Virginia, which has a moderate year round climate. Sure, we have our moments of extreme heat or extreme cold but by-in-large we're the Baby Bear of temps - not too hot, not too cold.
Remember, I have a total of 2 registers in my basement... During the coldest week last winter - where temps were in the mid-20's with a foot of snow on the ground - my trusty Acurite Monitor read 63 degrees.
During the hottest week this past summer - the average highs reach 95 everyday for 4 days - the max temp reached 74 degrees, and that was in the room exposed to the double doors.
So not too bad. I was able to get my video game room up to 67 degrees with a $50 plug-in heater. I did not need to add A/C, the 74 was mostly in the afternoon - in the evenings it dropped back down to 70-71.
To all my peeps in Green Bay Wisconsin - you may need to supplement your basement with a heat boost.
To all my peeps in South Georgia - you may need to add an AC boost.
I have a separate article coming soon that lays out your options, my recommendations and what it might cost.
3. How are You Going to Use Your Basement - Just Kickin' it or Living In It?
Finally, what you plan to do in your basement may affect your decision on whether or not spend the extra money to get your temps perfect and controllable year round.
If you're just gonna play some video games or watch movies or host a poker night or two then you're probably good to go with less precise control over the temps.
But if someone is going to be down there a lot, like living there, or you're going to use it as an office (that you actually work in) then you might want to make sure you have control of the temps.
Alright, hopefully that will get you started. If you think you'll just need a bit of extra heat (like me), read my recommendations on heating your basement here.
Do you have a specific question or comment on basement HVAC? Leave it in the comments below - I answer ALL questions.
Cheers - Jason
Other Hot and Cold Links:
- How do you finish a basement? Here the 8 major phases.
- How much would finishing a basement cost?
- How to install a basement register.
- Framing around duct work.