Siding and Insulation Help Needed – Pics Added
Midwest (zone 5b) ranch home (1500 sq. ft.) built in 1974.
– 2×4 fiberglass bat filled walls
– black fiber board sheathing (no WRB or felt)
– Original T1-11 cedar plywood siding (tested small amount of lead present in paint)
– Some sort of thin flexible WRB with foam insulation… prob not flashed properly judging by the quality of what I have seen so far
– Vinyl siding on top
– Aluminum flashing around most of the trim/windows/doors
– front of home has brick veneer instead of vinyl
– Existing windows are (5 total) 60″x 48″ double pane horizontal sliders and a couple smaller ones…that are in decent shape.. but as expected probably leak a good amount of air
Vinyl seems to sagging in some areas and poorly installed. Mainly in soffit and fascia where the weight is starting to pull old nails out and fascia is probably getting a good amount of water behind aluminum flashing
Goal – Would like to install LP SmartSide instead of vinyl and if possible without too much $/labor add some insulation and air tightness.
Not aiming for passive house…. just a boost of performance without getting too crazy.
Seems fiberboard handles moisture well and helps with sound (near a busy road so that is a plus). Plus adds a bit of R-value.
Assuming leaving this in place would be wise.
With having large overhangs and some sort of WRB in place.. I’m hoping the original siding isn’t in too bad of shape.
Thinking maybe should leave in place if no rot?
Insulation / New Siding
This is where the many options gets daunting.
Cheapest and easiest option I am guessing would be:
– Install a proper WRB – maybe fluid applied type onto original plywood siding?
– Add minimum amount of exterior foam – 2″
– Install the LP SmartSide
I know the optimal solution performance wise (for sides and rear of home), would probably be:
– install 4-6″ of exterior rigid foam on top of original siding
– move out windows/doors (replace with better units?)
– WRB and rainscreen
– LP SmartSide
My concerns for this option is cost.. and time. Also some details like bumping out the electrical/gas meters, attached deck in backyard, extending foam into ground around basement walls, etc.. but would provide a large upgrade to building envelope.
Is there a middle of the road solution?
What would give a boost in performance without driving up cost and labor too much?
Would adding interior insulation instead of exterior be a good option in this case since the front of the home is brick?
And if adding interior insulation, what would be the best option for this existing wall assembly?
What method/option do you think would work best?
Vented attic will be R-60 cellulose
Basement walls will be R-20 unless extending exterior foam down
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