 |
07-11-2022, 01:30 PM
|
#1
|
Mini-Skoolie
Join Date: Oct 2020
Location: DFW, TX
Posts: 24
Year: 1998
Coachwork: Carpenter
Chassis: 3800 International
Engine: DT466E (?)
Rated Cap: 48
|
Shade rack or second roof, how to stay cool in Texas?
Hello all! I've got a '98 International that I'm converting into a tiny home. I have electricity, 60 amp box, but am REALLY trying to minimize usage.
I'm in Texas, or currently the armpit of Hell, and I'm having trouble keeping the bus cool. My question is, what would be the most effective course of action to cooling the bus from the outside? It's as insulated as it's going to get from the inside. It's white and has elastomeric roof, along with wool insulation and all windows covered in radiant barrier. My thoughts are as follows;
1. Build a rack on the roof to stretch shade cloth.
2. Build a second roof/siding to insulate the metal.
My concerns
1. Will that cause wind issues? Will there be a noticeable reduction of heat due to the shade? It is the cheapest/easiest/fastest route, but will it help any?
2. Will the added weight push the bus over it's 26,000lb limit? It's an 8 window bus.
A carport would be best case, but it's cost prohibitive currently, plus trying to stay away from permanent structures.
Anybody have any experience or tips/tricks? The advice would be much appreciated. 🙂
The picture is of my very janky but slightly effective attempt at shade from a fence line. I have added more since then.
|
|
|
07-11-2022, 04:22 PM
|
#2
|
Bus Crazy
Join Date: Jul 2021
Location: Southern Oregon
Posts: 1,624
Year: 1996
Coachwork: AmTran (Now Navistar)
Engine: DT444E (7.3L) International
Rated Cap: 31,800 pounds
|
ANYTHING that will block direct or indirect solar heating of the main roof (and the sides) will reduce solar heating of the bus. Even a tarpaulin 6 inches off the existing roof will create an air gap between the tarp that absorbs the heat and the bus roof.
ANYTHING that shades the roof and or sides from the sun will reduce the solar heating of the interior.
Also, if you have access to a water source..... municipal, well, creek/pond you could install an evaporation cooling system. This can be anything from a few sprinklers along the roof (not the best solution due to minerals in the water crudding up your exterior) to those little mister systems mounted in a way to surround the bus in an evaporation cooled layer of air. NOTE: Misters do not work in high humidity.
As we plan on a lot of boon docking, thus limited water, our build incorporates a full coverage solar block consisting of solar panels, wooden access walkways, and wooden coverage resembling (but not) a deck.
__________________
YouTube: HAMSkoolie WEB: HAMSkoolie.com
We've done so much, for so long, with so little, we now do the impossible, overnight, with nothing. US Marines -- 6531, 3521. . . .Ret ASE brakes & elect. Ret (auto and aviation mech). Extra Class HAM, NAUI/PADI OpenWater diver
|
|
|
07-11-2022, 04:26 PM
|
#3
|
Bus Nut
Join Date: Feb 2019
Location: Communist State of New Jersey
Posts: 964
Year: 2004
Coachwork: IC
Chassis: CE200
Engine: T444e
Rated Cap: 27,500
|
Drive the bus to a cooler climate.
OR
Completely cover the bus with shade and get a killer A/C capable of offsetting the thermal action of the 102 degree DFW summer sun.
|
|
|
07-11-2022, 04:43 PM
|
#4
|
Skoolie
Join Date: Dec 2014
Location: central texas
Posts: 173
Year: 1990
Coachwork: Thomas/International
Chassis: 3700
Engine: 7.3
Rated Cap: 72
|
Heat
As he said, anything helps.
I have a full length roof rack with metal roofing 2in gap down the sides, on the sides the lower 2ft of the outside walls are not covered, on this 12 window bus most of the windows are insulated and covered, on the inside I have 1in insulation board down both sides, ceiling has original 2in fiberglass,
Before the roof n outside walls were covered the window unit could not cool it down if temp was 89 or higher, after the rack it works good to 100, less good higher than that, but liveable with fans, is a 12k or 15k window unit.
Search bubb for pics
|
|
|
07-11-2022, 07:40 PM
|
#5
|
Bus Crazy
Join Date: Apr 2020
Location: Northern California (Sacramento)
Posts: 1,635
Year: 1999
Coachwork: El Dorado Fiberglass
Chassis: Ford E450
Engine: V10 Gas
|
Tough one. I'm still thinking about how best to shade the bus.
Cutting direct solar gain (except for solar panels) is key. That means having an air gap and circulating air between the shade and the top/side of the bus.
I'm looking at a few tarp designs that use fiberglass tent poles. It will be only when the bus is parked, of course.
Just having windows blocked from the inside makes a huge difference, of course.
|
|
|
07-11-2022, 08:16 PM
|
#6
|
Bus Crazy
Join Date: May 2018
Location: topeka kansas
Posts: 1,820
Year: 1954
Coachwork: wayne
Chassis: old f500- new 2005 f-450
Engine: cummins 12 valve
Rated Cap: 20? five rows of 4?
|
sprinklers....
fastest way to cool it, make it rain on the bus.....
shade with an air gap. the bigger the air gap the better. meaning air gap between the roof and what ever is providing the shade.
william
|
|
|
07-11-2022, 08:47 PM
|
#7
|
Bus Crazy
Join Date: Jul 2021
Location: Southern Oregon
Posts: 1,624
Year: 1996
Coachwork: AmTran (Now Navistar)
Engine: DT444E (7.3L) International
Rated Cap: 31,800 pounds
|
Quote:
Originally Posted by magnakansas
fastest way to cool it, make it rain on the bus.....
shade with an air gap. the bigger the air gap the better. meaning air gap between the roof and what ever is providing the shade.
william
|
I'm trying to figure out what to do with the condensate from the air conditioners. Perhaps misting the air gap would be effective. Though then there would be less heat load and so less AC operation and less condensate. LOL
__________________
YouTube: HAMSkoolie WEB: HAMSkoolie.com
We've done so much, for so long, with so little, we now do the impossible, overnight, with nothing. US Marines -- 6531, 3521. . . .Ret ASE brakes & elect. Ret (auto and aviation mech). Extra Class HAM, NAUI/PADI OpenWater diver
|
|
|
07-12-2022, 06:32 AM
|
#8
|
Bus Geek
Join Date: Jan 2019
Location: Philadelphia
Posts: 7,033
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466e
Rated Cap: 65C-43A
|
I think good interior insulation alone can be sufficient. I have 1.5" of XPS foam between my ribs and another 3/4" of XPS covering that and the ribs on the interior. On a 95°F day with my bus in direct sunlight (and all the windows open), the roof was measuring 135°F but the ceiling inside was just 98°F. So shade would have only been good for 3°F which isn't very significant.
With lesser quality insulation (like factory fiberglass) that is only between the ribs, and/or with the steel headliner still in place, the thermal transfer through the roof will be much more severe and shade would be much more important.
|
|
|
07-12-2022, 08:50 AM
|
#9
|
Bus Crazy
Join Date: Nov 2010
Location: Andrews,Indiana
Posts: 2,459
Year: 1991
Coachwork: Bluebird
Chassis: AARE
Engine: 3116 Cat 250hp
Rated Cap: Just the two of us.
|
The shade produced by my solar panels makes a noticeable difference between the area that has panels and the area that doesn't. I would think that anything that makes shade would make a difference.
The "Saudi" MCI MC5 had a unique double roof but, from what I have read didn't make much difference sitting still.
|
|
|
07-12-2022, 03:54 PM
|
#10
|
Bus Crazy
Join Date: Jul 2021
Location: Southern Oregon
Posts: 1,624
Year: 1996
Coachwork: AmTran (Now Navistar)
Engine: DT444E (7.3L) International
Rated Cap: 31,800 pounds
|
Quote:
Originally Posted by musigenesis
I think good interior insulation alone can be sufficient. I have 1.5" of XPS foam between my ribs and another 3/4" of XPS covering that and the ribs on the interior. On a 95°F day with my bus in direct sunlight (and all the windows open), the roof was measuring 135°F but the ceiling inside was just 98°F. So shade would have only been good for 3°F which isn't very significant.
With lesser quality insulation (like factory fiberglass) that is only between the ribs, and/or with the steel headliner still in place, the thermal transfer through the roof will be much more severe and shade would be much more important.
|
Some of us don't have the luxury of decreasing ceiling height with insulation. LOL Though we are now considering (and likely not going to) a raise down only the center of the bus, dependent upon the width of solar panels chosen.
I think you're missing a variable though on your 3 degrees figure. If you didn't have ambient air cooling the inside ceiling to ambient temp the thermal transfer would build and continue to warm the interior. With windows closed and depending on AC, that could become a factor. And believe me, if it's 98, I am not going to be allowed to open windows. The AC will be running, even if the genset is required for the power or we will be driving down the road to cooler temperatures........ that or one of us will end up in a deep hole.
We are either reinstalling teh original metal ceiling (after spray foam) and dealing with the thermal bridging or going with super think wood or synthetic material over the ribs. At 6'1" and not doing a roof raise, we have to conserve vertical clearance for my mush bucket.
__________________
YouTube: HAMSkoolie WEB: HAMSkoolie.com
We've done so much, for so long, with so little, we now do the impossible, overnight, with nothing. US Marines -- 6531, 3521. . . .Ret ASE brakes & elect. Ret (auto and aviation mech). Extra Class HAM, NAUI/PADI OpenWater diver
|
|
|
07-12-2022, 03:55 PM
|
#11
|
Bus Crazy
Join Date: Jul 2021
Location: Southern Oregon
Posts: 1,624
Year: 1996
Coachwork: AmTran (Now Navistar)
Engine: DT444E (7.3L) International
Rated Cap: 31,800 pounds
|
Quote:
Originally Posted by somewhereinusa
The shade produced by my solar panels makes a noticeable difference between the area that has panels and the area that doesn't. I would think that anything that makes shade would make a difference.
The "Saudi" MCI MC5 had a unique double roof but, from what I have read didn't make much difference sitting still.
|
Yeah, without air flow the secondary roof can't do much. Fans might have helped but if it depended on forward speed for air movement, it's not going to help when sitting.
__________________
YouTube: HAMSkoolie WEB: HAMSkoolie.com
We've done so much, for so long, with so little, we now do the impossible, overnight, with nothing. US Marines -- 6531, 3521. . . .Ret ASE brakes & elect. Ret (auto and aviation mech). Extra Class HAM, NAUI/PADI OpenWater diver
|
|
|
07-12-2022, 11:06 PM
|
#12
|
Bus Nut
Join Date: Jul 2017
Location: Rapid City, SD
Posts: 993
Year: 2001
Coachwork: Blue Bird
Chassis: CS RE
Engine: ISC 8.3 L 260 hp
Rated Cap: 36
|
You could build a metal frame on top your bus a minimum of 6 inches above the roof with sliding extensions so that it could overhang the front rear and sides of the bus a few feet when parked. They make shade cloth large enough to cover greenhouses in the summer. The shade cloth could go over the bus pulled tight and be anchored to the bottom of the bus body or the ground.
The shade cloth would provide shade while allowing air circulation and is not as effected by wind as a tarp and allows rain through so it is not as likely to get smashed in a thunderstorm. The shade cloth is available in different densitys to allow varying amounts of light.
Ted
|
|
|
07-16-2022, 09:30 PM
|
#13
|
Mini-Skoolie
Join Date: Jun 2020
Posts: 25
|
Use metal conduit and a tarp to make a low dome tent. I bent the conduit, crossed over and tied in the middle, ends friction fit (crammed) to convenient corners on roof racks. Tarp gets tied to racks too. Big air gap, doesnt interfere with maxfan, looks kinda cool, and rain goes right off
|
|
|
07-16-2022, 09:31 PM
|
#14
|
Mini-Skoolie
Join Date: Jun 2020
Posts: 25
|
Tarp Tent
The back of ours is all solar like most folks. The front end has the same elevated "racks" to be used for kayaks, whatever. But when we are parked, the tarp tent goes on. Two 12ft lengths of metal conduit, slightly bowed to create a dome, crossed over like an X, tied together at the crossover, and friction fit (crammed) into corners of the racks. Tarp goes silver side out and gets multiple tie-downs all around the rack rails. Creates a dome tent which is high enough that exhaust fans arent interfered with. Rain rolls right off. One hint for anyone trying this: vinyl or poly conduit melts and deforms almost immediately.
|
|
|
 |
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Threads |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|