Last year, a national "handyman" company found on Angie's list built a custom trellis for me for about $1000 which included 13 hrs of labor and the purchase of all materials on my crdit card. If I had been unable to accompany the young man to Home Depot for the purchase of materials, the comapny would have charged me cost plus 100% for the supplies.
I designed the trellis consisting of 3 connected panels, each 9 feet tall by 4 feet wide. It was all custom because I needed sturdy panels to hold heavy vines - he used 1x2's for the lattice parts and 2x6's for uprights and cross pieces with a 16' 2x8 at the top. All 4 supports for the structure were buried in holes 2 feet deep and set in quikcrete. All crosspieces and and trellis parts were routed and screwed so should one of the 1x2's need replacing, it could be done without taking the whole thing down. It's beautiful and extremely sturdy.
I hope this gives you some idea of costs involved and good luck with your project.
Pat in PA
I live in Central PA (Harrisburg) so prices may be somewhat less than in a metropolitan area.

Sometimes a price reflects the value of the product. Sometimes it reflects the cost of producing it. Sometimes the cost of producing it is a reflection of general overhead, or effeciency, or uncertainty, or a lack of desire to do it. There are so many variables.

Does it make sense that most landscapers would be better than most full time wood craftsman at constructing at constructing a wood structure? Does it make sense that a full time wood craftsman might be more efficient at doing it?

It is possible that the landscapers that you got quotes from are very experienced in building these both in terms of craftsmanship and all the ins and outs of what makes this different from just another woodworking project. Knowing those differences might make their product more valuable, or might add to the expense of building it over the carpenters' product.

I do work with many landscapers and know that sometimes they will add a "PITA" (Pain In The Neck) factor to a price to either drive the client to finding someone else to do a part of a job or to cover the expense of the difficulties they know they will encounter. That way they don't lose either way. It could be that your landscapers are doing that.

Try to get a reading of how enthusiastic the landscapers are about doing this part and how receptive they are about you getting someone else to build it. It would be foolish to pay someone more if they really don't want to do it.

If they seem like it is important for them to do it and explain why their product will be worth the difference, you'll have to make the judgement.

Not that it makes things easier, but you really need to see work that your prospective contractors have done. I used to work for a landscape design/build in Northern VA; we had a dedicated staff carpentry crew, headed up by a phenomenal craftsman who did everything from framing to finish carpentry beautifully. Our custom woodwork was pricey, but flawless. On the other hand, there are a LOT of companies out there calling themselves carpenters. Just because some mope with a nailgun puts a sign on his truck doesn't make him a good carpenter.

Thanks for the replies.

All the contractors who have bid clearly want the job. I have not seen the work of the landscaping contractors, but since both are recommended by word-of-mouth, I think they will be fine. Regarding the general contractors and woodworkers, I have seen only photos of their work.

The design I have is also a 3-section design, with the side sections 3' and the middle section 8', for a total of 14' length. The middle section is 10' high; the sides 8.5' high.
The posts are 6"x6" set 3' into the ground in concrete. The bottom and top frame are 2"x4". Top 1.5' of each section are 1"x1" upright rights. The remainder space is filled with pre-fab lattice framed in cedar cap on all 4 sides. I will be growing pyracantha and roses up it, so it needs to be strong.

One question I have is what sort of joints should be used to connect the structure, and then the interior work. One GC said he was planning to butt them with screws and nails. That did not sound encouraging to me. I have seen some garden structures at a local arboretum that have beautiful joints that "lap" inside each other (not sure of the technical term here; sort of like mortise-and-tenon), and that is what I'm looking for -- both for the sturdiness, and the looks. I have asked the same question to the landscaping contractors, and would like to ask here as well.

My preference for trellis joinery for exterior locations leans towards the fine craftsmanship side.
The use of mortise and tenon , stub tenon joints, lap joints, cogged lap joints and pole plate joints hold up beautifully to the harsh weather conditions.

Not only does a craftsman need to know how to mechanically make these cuts but also needs to know the expansion and contraction rates of their wood.

A beautiful blind stub tenon is not a thing of beauty anymore if it swells and splits out the sides of your structure.

For this kind of fine craftsmanship you are purchasing knowledge, dedication to craft and experience as well as product.

In some cases a glued, screwed and butt joint can be just as effective as a doweled joint in the hands of a fine craftsman who has evaluated his material , client, and climate forces.

but my preference has always leaned towards beautiful well constructed craftsmanship.

Photo ®
{{gwi:53257}}From portfolioMay08.jpg

"trellis" doesn't seem to mean very much when it comes to details does it? Those 8' x 4' panels at Home Depot range from $13 to $26 and cedar costs more but none of them fit into a Honda Civic. The posts you attach those panels to need to be attached to the ground somehow,another variable, how deep do you want/have to go, concrete, metposts, what?

An efficient 'support' for roses and Pyrocantha would probably not be made from wood but what does it look like? If you buy unseasoned wood and cut the most perfect joint in it that look will be temporary.

You may want to think about where you live because building with green wood is a pioneering speciality and joining wood was adapted to those circumstances.p>

Thanks for weighing in on the joinery issue. That's a stunning trellis, Deviant! I think the issue of "fine craftsmanship" has clarified things some more. I guess I'm looking for a quality craftsman, like Marcinde also describes. That helps me evaluate the bids I have so far.

At the same time, I don't need high-end tropical woods for this project since it will be covered up with pyracantha. Pressure-treated wood should be suitable.

Here is my next question. Are there grades of PT wood? If I want the best quality PT wood, what should I be looking for?

Thanks for all your help so far.

deviant's trellis is gorgeous, but since you're looking at using pressure treat, "Not only does a craftsman need to know how to mechanically make these cuts but also needs to know the expansion and contraction rates of their wood" is ESPECIALLY critical here. The p/t wood we're getting in our area (up in Baltimore, they're probably pulling from the same mills we are down here) is pretty green still, and prone to movement. I don't know exactly what the design of your piece looks like, but given that you're a) using p/t, and b) having it covered with a climber, the guy stating he'll use a butt joint with screws is probably on the right track. It saves labor dollars, and since you're using a wood that WILL warp, check and crack- sounds like the way to go. Done well, it can still be really attractive. My carpentry sub of choice did a lattice fence of p/t 2x2s about ten years ago, and rather than lapping the 2x2s he used a deck screw at every point where the members crossed. It still looks great today, and there's enough mechanical attachment that the wood has barely moved.

dd, regarding that photo- all I have to say is "homina homina homina."

Trying to understand the discussion on joints. I hear you saying that PT wood for trellis is likely best off with butt joint because of expansion/contraction.

What types of wood work best for inset joints?

Also, my bids are varying widely on cost of materials -- why is that if they are all quoting PT wood? Are there grades of Pt wood?

Thanks

I have no idea of the types of pressure treated woods that are used in MD but here on the Left Coast our pressure treated wood would never be used to build a trellis, unless the trellis was not going to be seen in public or if it had any visual aesthetic presence at all.
Pressure treated wood here comes horribly marked up due to the pressure treated vacuuming process. It has 1/2" long imprintations impaled into the wood on both face surfaces and is either dyed a greenish color or a dark brown color dependent on the type of preservative that was used .

We use redwood, cedar or ipe ( a tropical hard wood ).

The wood that was used on the trellis in the photo above was Port Ordford Cedar.
The wood that was used on the trellis below is redwood.
photo ®
{{gwi:53258}}From portfolioMay08.jpg

dd- our p/t comes from the lumber yard more presentable than what you're describing; the carpenters will often run it through a planer to pretty it up a bit anyhow, since even the "select" boards aren't always in the greatest shape. Don't get me wrong, it has none of the richness and character of natural cedar or redwood, but we've also got a slightly different architectural style here- lots of brick and white-painted wood.

The reason I'm considering PT for this project is that the evergreen pyracantha will likely completely cover the trellis. That said, the vine will be heavy, and so the trellis needs to be strong enough.

I thought that there must be some difference in the way the pressure treated wood is used and manufactured between the two coasts.

Pressure treated wood in California is not a thing of beauty.
It has deep impressions all along the face . It looks like someone took a staple gun to it and then pulled all the staples out.
It is either green in color or a deep dark brown color depending on the type of preservative that was used.
It it used primary in the landscape construction field as deck joists and beams and in certain cases , post and ground to wood contact path construction.
We don't even use it as the top boards on a deck - unacceptable quality and look, not to mention the toxicity .
One would only use it when building a trellis if the trellis was going to be completely hidden or covered.
Most of it is very green wood ( unseasoned ) and will wrap as it shrinks.
Contractors need to be extremely knowledgeable in pairing up their galvinized Simpson ties to PT wood. Some of the new preservative used chemically react with the gal. metal ties and the ties corrode.
There have been several law suits and lots of public information distributed about this since the new ( actually it's not so new , it's been around for about 10 years now or longer ) Pressure Treated Preservatives have replaced the old arsenic based chemical preservatives.

For more info on the corroding issues of metal connection ties and how metal reacts to the preservative forumulations in the wood you might want to read the Simpson Tie website or Fine Homebuilding, This Old House or if you are in the trade Journal of Construction.

Decide which type of the two groups of providers you want to use and then get enough bids/estimates for a middle range to emerge.