Horizontal furring for rainscreen
pietrasm5
| Posted in General Questions on
Is there any reason I couldn’t just use ‘blocks’ of 1/2″ plywood or even just cut pieces of Cor-a-vent behind my horizontal furring strips at nailing locations? All I see is complete vertical strips of strapping/plywood/Cor-a-vent with the horizontal furring over that. I feel like using pieces behind nailing locations (instead of full vertical strips) would both save money and allow for increased lateral airflow. Am I missing something?
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Replies
If you don’t care about labor it might be a little cheaper, but then you will probably use more fasteners so maybe not
There's a lot of unstated information here to be able to answer "why can't I just..." questions.
We infer that you're using a type of vertical siding, if you're asking about horizontal furring.
Are you using both horizontal and vertical furring over exterior insulation that's compressible? Do you need the ability to level the furring plane over top of compressible insulation, and you do you need the load distribution of full vertical strips?
Do you need the screw holding capacity of a horizontal strip spaced off the wall? Do you only need a ventilated horizontal strip directly against sheathing? Could you just use horizontal Cor-A-Vent strips and don't need vertical furring at all?
Do you know where your stud locations are? If so, then even spacers made of 1/4" plywood would be enough. The key would be to use fasteners long enough to attach your horizontal furring through the spacer, the sheathing, and a good 1 1/2" into your studs.
This may or may not meet local codes, which could require a thicker spacer. But it would certainly work.
You'll want to give some thought as to nailing surfaces around doors and windows, as well as building corners.