LP vs spruce siding durability
Hello, how do you think the durability compares for LP smartside siding vs spruce? The local lumber mill sells spruce as an option and fir & larch as the other option. #2 spruce is essentially the same price as 6” lap siding from LP. Obviously local real wood products are superior in esthetics, environmental impact, etc but what about durability? I’m very familiar with the durability of the lp smartside in our climate, but don’t have much to go off of for spruce. Fir and Larch is roughly 2x the cost of spruce, is it 2x as durable? LP board and batten is the dominate cladding choice in my market right now.
More context: climate zone 6, dry climate, rain screen, 3’ overhangs in most areas, with some very large overhangs over covered patios. When it does rain, it seems to rain sideways more often than a simple drizzle.
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Spruce is not very rot-resistant so I think LP Smartside would win if it were a demanding situation. But a dry climate with a rainscreen and large overhangs would allow cardboard to work as siding, so I wouldn't worry about spruce. I have only used spruce clapboards once or twice and they were radially sawn, vertical-grain, and I found them to be fairly brittle compared to the red cedar I'm more familiar with.
Thanks Michael! We get ~18-20" annual rainfall so it's not DRY. But it is in the dry area of the climate zone map. Unfortunately, cedar is not readily available from local sawmills, otherwise, I would opt for cedar. Any thoughts on fir and larch siding vs spruce from a durability standpoint?
Fir is used for exterior posts and beams quite often and they seem to hold up, but they have excellent drying and are quite thick so I'm not sure that translates to a 3/4" thick siding product.
Funny, I'm just texting with a client now about various cedars, fir and larch as siding. There are a lot of variables so it's really hard to say. Cedar can be eastern white or western red, or eastern red which is really a juniper, or Alaskan yellow which is really a cypress. They each vary depending on how they're cut--rift and quartered material will move less and usually last longer than flat-sawn material; heartwood is usually more rot-resistant than sapwood. Fir can be pretty rot-resistant but old material might have growth rings 1/16" apart (or closer) while modern material may have growth rings up to 1/4" apart--that seems to translate directly to rot resistance. I don't have first-hand experience working with larch (aka tamarack, or in Maine, hackmatack) but it's traditionally used as mud sills and barn floors, so I know it's tough stuff. Around here, larch trees have a lot of small limbs so the lumber is probably knotty, though older stands may be more clear.
I recently learned that Lifespan Pine is now making clapboards. I have used their exterior trim material and it's pretty decent--plantation-grown radiata pine with a light preservative treatment and primer.
All good points. In my area, it’d be western red cedar I imagine. Unlikely that eastern white cedar is being shipped 3/4 way across the country. Cypress is pretty rare to see in this area as well. As an anecdote, my dad built a log house roughly 30 years ago in Michigan with a western red cedar log package and it’s held up beautifully with minimal maintenance.
I called another mill 100 miles away that carries cedar, fir, accoya, thermally modified fir, etc. he recommended cedar as the best bang for the buck. He also commented that most of the high end homes are spec’ing fir siding. It’s definitely good looking.
Pioneer Millworks, by any chance? They show a nice range of options on their website.
The spruce will last fine in that climate, with the understanding it will need to be re-painted every so often. If there are problematic areas such as difficult flashing details, splash back from the ground etc. could lead to premature deterioration.
The real enemy will be the sun on south facing walls, but that will be for LP as well.
Larch all the way. My siding, trim and deck boards are larch. I dumped piles of larch shavings in the compost pile and they won't start to decompose. It does require a little finesse. I predrill at many fasteners, and some boards have a mind of their own as they dry, even when stickered.
Michael, it was 1st Choice Millworks out of Coeur d' Alene, ID. My local lumber mill, RBM has a little better prices for fir & larch but the prefinishing 1st choice offers looks excellent.
My local mill: STK fir & larch, 6” x 3/4” profile is $4.57/sqft unfinished. #2 is $3/sqft. #2 spruce is $2.12/sqft.
1st choice is roughly $4.90 unfinished, $8.20 finished.
Beveled lap STK cedar siding from the local lumber supply is roughly $4.42/sqft.
6” lap LP is $1.82/sqft unfinished
Board and batten LP is $2.18/sqft unfinished.
Choices, choices, choices! LP is extremely popular here, even on multi million $ homes.