Through-the-door transfer grille?

[Puzzler]

I was wondering if anybody knew anything about the Tamarack "Perfect Balance" in-door air pressure relief system? It's basically a through-the-door transfer grille. Here's the website about it:

[NewportNic]

Usually the gap under the door is enough, if not maybe the door needs to be shortened. I have done this many times using a hand held power plane.

This should almost never be done in a commercial environment.

Klaus
Walbridge FM
"I'm one of those regular weird people." Janis Joplin born January 19, 1943

[khc95]

Usually the gap under the door is enough, if not maybe the door needs to be shortened. I have done this many times using a hand held power plane.

This should almost never be done in a commercial environment.

Klaus
Walbridge FM
"I'm one of those regular weird people." Janis Joplin born January 19, 1943

Why not in a commercial application ???

[NewportNic]

Because of fire breaks. Unless you know that a wall is not a firewall it should be treated as one. Altering the door invalidates its UL Fire rating which should match the rating of the wall.

An insurance inspector, local building inspector, or fire office will make you replace the door.

Klaus
Walbridge FM
"I'm one of those regular weird people." Janis Joplin born January 19, 1943

[jimj]

Usually the gap under the door is enough, if not maybe the door needs to be shortened. I have done this many times using a hand held power plane.

This should almost never be done in a commercial environment.

Klaus
Walbridge FM
"I'm one of those regular weird people." Janis Joplin born January 19, 1943



I hope your kidding!:LOL:

[NewportNic]

Why wouldn't you shorten a residential door, say after carpeting has been put in a house that has hardwood floors. If the door seals down to the carpet it is hard to open and the air can't get back to the return duct.

Klaus
Walbridge FM
"I'm one of those regular weird people." Janis Joplin born January 19, 1943

[jimj]

Unless your cutting off 2 or 3 inches your wasting your time.

[REP]

Sure is a lot cheaper than doing it right.

[acwizard]

i AM GOING TO GO ALONG WITH NEWPORT NIC, A 1 " DOOR GAP IN A RESIDENTIAL APPLICATION COULD EASILY PASS 150CFM OF AIR WHICH COULD SERVE A TYPICAL BEDROOM. i WILL AGREE A RETURN GRILL IN EVERY ROOM WOULD BE THE BEST. HE MADE A VERY VALID POINT ON WHY YOU WOULD NOT UNDERCUT A DOOR IN A COMMERCIAL BUILDING. IF A DOOR HAD A FIRE RATING THEN A SMOKE SEAL WOULD ALSO BE REQUIRED AS PER UFC.

[jimj]

i AM GOING TO GO ALONG WITH NEWPORT NIC, A 1 " DOOR GAP IN A RESIDENTIAL APPLICATION COULD EASILY PASS 150CFM OF AIR WHICH COULD SERVE A TYPICAL BEDROOM. i WILL AGREE A RETURN GRILL IN EVERY ROOM WOULD BE THE BEST. HE MADE A VERY VALID POINT ON WHY YOU WOULD NOT UNDERCUT A DOOR IN A COMMERCIAL BUILDING. IF A DOOR HAD A FIRE RATING THEN A SMOKE SEAL WOULD ALSO BE REQUIRED AS PER UFC.

Take a flow hood and check cfm with the door open and the door closed, with a 1" undercut on a bedroom door you will have a serious cfm drop. That does not even come close to the negative pressure issues it throws the rest of the home into.

:payattention:

[energy_rater_La]

possibly if the room had a single supply
add multiple supplies and an undercut door doesn't return
enough air.

OP I haven't seen (or tested) this product, but depending on the size
of supply ducts, number of supply duct and the amount of air that this
product would move..it could work.
In some of the info it should tell the cfm of air return it allows..I may have
missed reading it..that along with the size of ducts and number of ducts
will be the determining factor.

another factor will be door type..hollow core doors have a solid piece at the
bottom of the door for strength beyond this the door is hollow with cardboard
spacers. I'd never cut the solid piece out totally, but instead would locate
the grill above the solid bottom. Is this applicable for your situation??

best of luck, and thanks for the link..I'm sending it along with my questions
to some of the folks I work with for their input also. It would be a nice alternative
if it works. I may recommend it myself!

[tipsrfine]

Looks like spam to me. Surprised the op didn't get deleted.

[Stamas]

Unless your cutting off 2 or 3 inches your wasting your time.

Ditto

[acwizard]

[QUOTE=jimj;9105741]Take a flow hood and check cfm with the door open and the door closed, with a 1" undercut on a bedroom door you will have a serious cfm drop. That does not even come close to the negative pressure issues it throws the rest of the home into.

I am not disagreeing that a doorway with a free area of 2400 square inches open versus closed with 30 square inches would not be a serious cfm drop, but my point is it could pass 150cfm at 750fpm. This would not work for all rooms , but it will work for some. Obviously you couldn't dump more than 150 cfm out of the supply into this room in this example.

[Puzzler]

Looks like spam to me. Surprised the op didn't get deleted.

Harumph. :argue: Why would somebody pointing out a new product that could make your customers more comfortable be spam? Are you unaware of the many comfort issues caused by airflow problems? I would give you links to RESNET's Energy Smart contractor site or the Building Performance Institute (BPI)'s website, but I guess you'd think I was trying to 'sell' that, too.


possibly if the room had a single supply
add multiple supplies and an undercut door doesn't return
enough air.

OP I haven't seen (or tested) this product, but depending on the size
of supply ducts, number of supply duct and the amount of air that this
product would move..it could work.
In some of the info it should tell the cfm of air return it allows..I may have
missed reading it..that along with the size of ducts and number of ducts
will be the determining factor.

another factor will be door type..hollow core doors have a solid piece at the
bottom of the door for strength beyond this the door is hollow with cardboard
spacers. I'd never cut the solid piece out totally, but instead would locate
the grill above the solid bottom. Is this applicable for your situation??

best of luck, and thanks for the link..I'm sending it along with my questions
to some of the folks I work with for their input also. It would be a nice alternative
if it works. I may recommend it myself!

Thanks, energy_rater_LA. I would not have considered the door material if you had not pointed it out. The product website says, "At 2.9 Pascals achieves 222 cfm of air flow." I'm not sure what to do with that info, though. I had thought you wanted an air flow rate equivalent or greater than the supply, so seeing the air flow tied to a pressure differential throws me off. Makes sense, but now I guess I will have to dig through some materials to figure out how to calculate recommended room-to-room airflow. Do you know what the recommended max pressure differential should be? Something in the back of my head is saying 1 Pa. Still not sure how to evaluate that door, though.

Darn shame more HVAC contractors don't think outside the box. Air Flow Dynamics is a really weak spot in our industry - I guess so much so that some consider it spam! Grumble, grumble. It's just not covered in the trade schools, and the knowledge therefore doesn't get passed on. Harumph. Trying to get feedback about a product that could help my customers be spam. Grumble, grumble.

[Puzzler]

Well, jeepers creepers, tipsrfine, I just took a look at your profile. You look like you are all over the energy auditor thing, BPI & all. So I retract my arguing smiley-faces. Still super-confused as to why you would accuse me of spamming... I saw an ad in Green Builder magazine for it, and got excited, and wanted to find out more. Spam? Spam! Still insulted, but I must say if you've got your BPI BA, then I will allow you your opinion. :) Have a beer on me: :bsing:

[tipsrfine]

Well, jeepers creepers, tipsrfine, I just took a look at your profile. You look like you are all over the energy auditor thing, BPI & all. So I retract my arguing smiley-faces. Still super-confused as to why you would accuse me of spamming... I saw an ad in Green Builder magazine for it, and got excited, and wanted to find out more. Spam? Spam! Still insulted, but I must say if you've got your BPI BA, then I will allow you your opinion. :) Have a beer on me: :bsing:

Tamarack has been discussed before at this site. I am fully in support of this product. The problem with your post was that it sent you directly to their website and it was your first post, which indicated a high posibility that you were a tamarack salesperson trying to get a free add on this site. Adds have to be paid for.
On the other hand, this link http://www.bestofbuildingscience.com/pdf/HVAC%20system%20pressure%20relief%20HEM_23-4_p42-45.pdf appears to be a more scientific study on the subject, and still accomplishes the goal of getting word out about RAP's.

[Puzzler]

Tamarack has been discussed before at this site. I am fully in support of this product. The problem with your post was that it sent you directly to their website and it was your first post, which indicated a high posibility that you were a tamarack salesperson trying to get a free add on this site. Adds have to be paid for.
On the other hand, this link http://www.bestofbuildingscience.com/pdf/HVAC%20system%20pressure%20relief%20HEM_23-4_p42-45.pdf appears to be a more scientific study on the subject, and still accomplishes the goal of getting word out about RAP's.

Thank you for the article! I started reading it, then realized I am going to have to focus on it rather than skimming, so I have printed it out & looks like will have to take some notes.

I had read the forum rules when I first joined, and didn't pay too much attention to the advertising rules, as I had no intention of advertising. I realize now that the mods don't have time to figure out who everyone is & what their association is with any given product, so my new rule is no links to products & services!

I wasn't actually trying to 'get out the word,' I just wanted feedback on if anyone had experience with that particular product, and what they thought of it. Any thoughts on how to do that in the future without breaking any rules?

[garya505]

Looks like you have to mount it in the bottom of the door, which wouldn't work too well in a hollow-core door as you would have to cut out the solid piece of the door bottom.

[tipsrfine]

Thank you for the article! I started reading it, then realized I am going to have to focus on it rather than skimming, so I have printed it out & looks like will have to take some notes.

I had read the forum rules when I first joined, and didn't pay too much attention to the advertising rules, as I had no intention of advertising. I realize now that the mods don't have time to figure out who everyone is & what their association is with any given product, so my new rule is no links to products & services!

I wasn't actually trying to 'get out the word,' I just wanted feedback on if anyone had experience with that particular product, and what they thought of it. Any thoughts on how to do that in the future without breaking any rules?

I don't really know. I've never really read the rules, just kind of picked up on them as I've seen others break them. Your's just looked fishy to me with it being your first post and with a direct link to a site selling something.

[energy_rater_La]

spam? think so...I don't know but it seems
that I've seen OP's input on misc threads.
did y'all look at the product?
think it may work??...seems to be ES approved.
if y'all have time I'd appreciate y'all's pov.
thanks