Wall construction?

[Ira]

Bruce, in Illinois, you want insulation. 3/4" straight ply is fine for certain areas, but up by you? No way.

Which way the foil faces is open to debate, and even a lot of plans don't take into consideration WHERE you live and where you're going to use the TD.

Down here in South Florida, I want all of outside heat to GO AWAY, so EVERYTHING faces out, including the floor insulation. Up by you, camping in cold weather, you want all of your body heat to stay IN the cabin, so you would do it the opposite.

Don't know what difference this makes with cheap HD foil-backed white insulation, but...

It can be 90 degrees out here by me, and when I open the door, it's COOL in there.

[Cary Winch]

Bruce,

The total amount of sidewall that is resisting heat loss is really pretty small on a standard 8' teardrop. While the insulated will help lower your condensation temps it is not necessary for most temps you will encounter. I have nothing against the insulated side walls, just a completely different design to work with. By the way, if doing a plywood side wall stick the 3/4" wall. It has enough stiffness you won't need a bunch of reinforcing. Unless you want to do the Roly thing and use 1/4" and frame it all up, you should see that thing in person it is amazing.

The biggest thing I tell customers when deciding their cooling options is think about the temps at night where you will be travelling. It does not matter the day time temps since you are not in it at night. Also keep in mind that a person generates 80-100 watts of heat. So, two people in the cabin will create enough heat on a cool fall evening that you will be opening windows. Keeping the cabin cool if the heat is generated from within (after dark remember) means the insulation will be working against you if anything. Make sure to have some good ventilation, roof vent, sunroof or fantastic fan or something.

What part of IL are you in?

Cary

[riverfront]

I am one hour (60 miles) south of the WI. boarder and 30 min(30 miles) east of the Mississippi river (Clinton, IA.). Northwest IL.

I will have an A/C for hot weather, A MUST! - Humid arround here! Have not thought about heat yet but will have to plan something even though I love cold weather! As I always say " If you don't like the seasons up here and esp. the cold then move south and stop complaining."

I asked you Cary because 1) you are a builder MFG.! 2) you live not that far north of me and have a similar weather system! I am willing to build what I need but with a tight budget I don't need over kill!

This is the perfact forum for guys like me and I really thank everyones input!!!!!

[Cary Winch]

Bruce,

I think you and I would get along famously!

The main reason I asked where you were is to see how far a drive to our shop you are. Looking at ours being built is generally a great crash course on ideas. If you are thinking AC, then even more reason. We have that one down pretty good and not every sees exactly how we do it without looking at one closely. You are most welcome to come here someday and hang around to get ideas. Plus we do sell some of our parts to that you might find handy.

Cary

[riverfront]

I know where Nacedeh is - I used to manage a marina in Dixon, IL. and the owner has land in your area - George Fictenmiller - Beautiful country up there!!!

I will have to take you up on that visit but I will have to find time to get away and untill this fall that will be a problem!!! The way things are going I am not getting the time to get started on the drop - At this rate I know I won't get things done by my Oct. 1 deadline but maybe Linda and I could get away then and stop up! Don't tell anyone but this anniversary will be a Motel and not the teardrop like we planned!

Maybe this is best so I make the right decisions!

[Cary Winch]

Bruce,

Ok, then I will plan to see you some time.

Giving yourself time to design and dream a bit always helps I find. I have a homebuilt airplane project right now that keeps evolving because I don't have room in the hangar to work on it. By sometime next year I can get to work on it and it should be pretty nice (in my head at least)!

Cary

[kayakrguy]

Folks,

A great discussion. I will have to soon decide, sandwich or open faced walls <G> I have two questions about sandwich and non sandwich construction.

First: IF the floor and roof ARE insulated (which I am doing) will insulating the walls make much difference in condensation when using the trailer? When storing it in Northern winters--very damp?

Second: When building sandwich contruction, what in the world do you use to attach 1/8 inch ply to walls and roof? I can only assume it would be nails and tightbond or some such--cannot imagine putting a counter-sunk screw in that stuff!

Thanks,

Jim

[Chris C]

Jim,

Just a suggestion here, but you might check out Steve Frederick's CD on building a trailer. http://www.campinglassics.com He builds with a sandwich construction.

It will sure eleviate a lot of your questions. I know it's frustrating right now, but it really is easy to build one of these things, and a little guidance sure is nice. Check it out.

[kayakrguy]

Chris,

Thanks for your reply. BEFORE I send Steve my money, which I am perfectly willing to do if I can get valuable advice and techniques for doing a good job, I would like to know the [b]PRACTICAL DIFFERENCES between the CONSEQUENCES of building sandwich or not.

In other words if the cost, weight and condensation and comfort questions are 'pretty even' ie--there is no dramatic advantage to sandwich construction, then, from a simple 'effort' point of view, I would not go sandwich, and would not need Steve's CD for ONLY that issue, though it might well be a good value on other grounds.

I would like some input about the practical consequences of one method of construction vs the other in the terms that my original note framed the question. There may be better questions, which I am prepared to hear, but until I hear them my questions are the 'occam's razor' for deciding between the different constructions of walls, because obviously one is simpler than the other.

Thanks again,

Jim

[madjack]

Jim, we built our walls with a single piece of 3/4 ply and the floor is a single piece of 5/8 ply...the roof is insulated...nothing wrong with insulation, I just don't see a need that justifies the trouble of sanwich construction...the volume of a TD is such that heating and cooling does not require massive efforts, as far as condensation goes, adequate ventilation will take care of most of that problem...with windows and a Fantastic brand roof fan/vent we haven't experienced any problems so far...also note that Camp-Inn and other manufacturers use single wall construction...the main advantage to sandwich wall construction is that it CAN be built lighter than a single 3/4 wall...my$.02 worth
madjack

[riverfront]

Madjack! In that one post I think you have helped me make my decision!

One question further - what is the weight difference between 3/4 ply and sandwich? If it is 20lbs per wall then sandwich my be wirth the effort but at 5 or 10lbs the work involved with sandwich isn't wirth the time!

In reality, cost and insulation(condinsation) being close to equal the weight is the only issue! Correct?

[Sonetpro]

Just my opinion but my other consideration was sound insulation. I run a genset often so I went with sandwich.

[PaulC]

I've run sandwich on both of mine.
1/2" outer, 1 1/4"x3/4" framing and 1/4" inner wall. The floor is 1/4" to road, framing as per Larry sorensen's build and 1/2" floor. Roof is 1/4" both sides with stringers. This is what I've done on number2(thinner in the main wall, floor and roof components) and it works out that it will be about 200lb lighter than the first one. It's insulated top,bottom and sides. Number two also has a hatch and extra cupboards and drawers which number one does'nt.

Maybe this will give you an idea on the weight saving gains you can make.

Cheers
Paul

[madjack]

Bruce, rough numbers...3/4 ply weighs 75#s, 1/2 weighs 50, 1/4 weighs 25...these are very rough numbers as other factors affect weight also (moisture, species, ect.)...now add in framing insulation and you can get an idea of weight diff...another thing to consider is your electrical...a little trickier in a solid wall but doable...but all things considered I still favor solid walls/floors(definitely floors)...no worry about getting cabinet attachment points perfect with solid walls...as to noise, with a fan or A/C going all I can say is "what noise"...the choice is up to the individual, which is one of the great things about building your own......
madjack

[kayakrguy]

Chris,

you forgot the c in campingclassics.com. Which c, you ask? <g> The one before the L....thanks for the link...I am reading there...

Jim