Here’s why your Range Hood doesn’t suck! (And kinda sucks)

Matt partners with Aprilaire to do a side by side comparison of the positive effects of make-up air when trying to ventilate a house.

Check out Aprilaire

Subscribe and follow my Podcast on Apple or Spotify!

Sign up for our twice-weekly newsletter:

To sponsor a video or advertise with us visit:

Huge thanks to our Show sponsors Builders FirstSource, Polywall, Huber, Rockwool & Viewrail for helping to make these videos possible! These are all trusted companies that Matt has worked with for years and trusts their products in the homes he builds. We would highly encourage you to check out their websites for more info.

[LumenCache]

Great demo. My first career was HVAC for Pharmaceutical Research Labs where flow tracking is everything. It's used to create positive or negatively pressurized zones to ensure fumes go where they need to go and not into the researchers. And all this with amazingly high cooling/heating efficiency thanks to ERVs. This was back in 1988! Took this long to become popular in homes. LumenCache can power this level of MUA and EFs just fine, plus monitor the pressure differential.

[petersharp]

Great demonstration. Another reason for makeup air is safety - if you don't have it, the path of least resistance for incoming air is the water heater exhaust if you have a gas water heater. Air pulled from there contains carbon monoxide.

[stucorbett]

We cook a lot and have a wolf setup with a 1500cfm exhaust hood. Just crack the window on the other side of the room and everything is good.

[LumenCache]

Funny story about Aprilaire: when I left commercial for residential integration, Aprilaire was the "Nest Thermostat" at that time (2006). I called support asking "How can I control a VAV box (Variable Air Volume)" and the support guy said "It's a HOUSE! Why do you need VAV?!" Fast forward to today: All the PH HVAC units are balanced damper systems with VFDs. I should have done product development sooner, but it is the market education rate that defines adoption rate. Thanks for Build Network Matt.

[crndg_]

I believe that any system which is taking conditioned air out of the envelope (dryers, gas hot water heaters, bath fans, etc) should have the option to supply its own make-up air. I had a wood-stove in the 90's which had a separate intake pipe for combustion air so it didn't evacuate air out of the house. I wish more things were designed with this level of thought.

[rlanderson]

Thank you, Matt, for a great visual. In a future video, can you address post construction troubleshooting and repairs? I often wonder if a homeowner will know if the powered makeup air equipment (and ERV or HRV's) are working or need repaired? Now retired, I had only built a few custom homes (less than 3000 sq ft) and a lot of Habitat homes and had passive makeup air through the HVAC in north Texas for simplicity.

[jlbreak]

The math at the end is the same that I use to decide which size pizza to get. Turns out, it is always the biggest.

[ringelos]

The custom makeup air built into the fumehood is cool. Biological safety cabinets work with a similar principle - air is fed from the top of the work surface and gets sucked in at the back, and gets recirculated through a filter. Everything in between exists in an isolated filtered air envelope (laminar air flow).

[Standard_Issue_Pedestrian]

Having it be triggered by the fan is tricky, because it should ideally open up whenever a bathroom fan is on, too. Same for if you have a traditional clothes dryer in your conditioned space. I have yet to find a clean solution that addresses ALL sources of house air being exhausted.

[oldtimefarmboy]

The purpose of vent air, from what I have heard, is to prevent the room from fogging up in the first place when you are cooking or taking a hot steamy bath or shower. A better test, I would think, would be how well the system prevents the room from getting all foggy from the moment the fog machine starts starts. If no vent air allows the room to get foggier and foggier over time and the vent air prevents it from getting foggier over time would be better proof of how allowing vent air.

[bj]

Have you ever tried AirScape's Make Up Air system? It's 1600 cfm capable and based on pressure.

[Alphasig]

You can also add a Shelly smart switch to damper so when it’s turned on it will tell another smart switch controlling make up air fan to turn on

[crashinc]

So he's correct I have a 350 cfm hood vent when it's on med or high it starts pulling air from my attic door on the other side of the house, my next project is to get that door to sealed better and some how add make up air to my house I'm trying to keep roofing penetration to a min

[nationsnumberchump]

Idk do the filters take out the smoke if the smoke is outside? We have alot of grass fires here in Oklahoma and Kansas. Seems like more crap to maintain and increases your electric bill. I just open the window when I know there isnt crap in the air outside and run my attic fan

[diehappy]

As I replace doors and windows on my 1952 house, do I need to think about adding make up air somehow? Talk to my hvac when my furnace craps out?

[DawgBone]

I have to ask the question....

How much money do you need to spend to make a "tight" house(upfront)?
Just to turn around and spend more money on a make up system?

VS....

The products that you're being paid to promote?

[krogg]

Flow is by the fourth power of the radius (assuming laminar) or higher if not.

[daveleary]

I had a Hauslane IS200 600CFM over island vent put in that doesn't pull air up and outside. It was originally setup to recirculate the smoke through charcoal filters but had such a lousy draw that I had them come back and vent it outside. I have a feeling some step was missed when they changed the direction of the air. There's a disk on top that needs to be turned for outside venting AND when I put my hands up to the fan in the hood the air blows on my hand, not pull. Does this sound like the vent isn't opened on top of the unit? It never had a great pull with the filters attached. The docs don't tell me if I can access the disk while it's up or if I have to drop the unit again. I'd like a neutral opinion, please!

[Salanan]

Me visiting Austin keeping my eyes peeled for real celebrities like Matt Risinger. 👀

[WawakGuitar]

There is a local restaurant in town that has no makeup air and a monster hood vent. The reason I know is when you go to open the front door, the suction is so hard that a child probably could not open it..