No soffits. what to do about insulation

Roofing/Construction Questions
#1

so i have a 1926 colonial (in northern new jersey) with a simple gable roof.
the roof itself is new. it has a continuous ridge vent, but no soffit vents.
the exposed rafters are seen from outside the home, but the clapboard (aluminium siding) extends up and there is no soffit, and no venting.

i am now looking to insulate this attic as i am looking to finish it for use as an office.

so, what do you think i should do to insulate. with no soffit vents, the ridge does little.
i’d prefer NOT to get a spray foam , as it’s quite expensive vs. fiberglass batts.

but if spray closed cell foam is the only correct way to do it, i’ll need to reconsider.

thanks for any help.
-thomas

#2

Go with the SPF, you won’t be sorry you did.

#3

Well 1 thing is for sure the shingle warranty is voided. The ridge vent does nothing without soffit vents. SPF is the way to go.

#4

ok- so foam is they way you guys think i should go.

but what if were to install soffit ‘buttons’-
i could get a few in for each rafter bay…
then could i go with the less expensive fiberglass batt situation?

or would is there not enough air being circulated with just those round soffit vent ‘buttons’ ?

#5

A good candidate for Smartvent.

#6

Smart Vent at the eaves during the roofing process.

Insulation baffle vents stapled to the underside of the decking boards to allow unrestricted airflow upwards.

Shingle Vent II Ridge Vent at the peak.

Insulation inside, using the highest R-Factor that will fit properly.

Ed

#7

too late for smartvent. the roof had just been replaced…
unless you are suggesting removal of some of the shingles to get the smartvent installed.

are there any retrofit solutions for a home with no soffits?

i thought i read about small round vents or ‘buttons’ that i could drill into the clapboard to get some air into the rafter bays…

thanks.
-thomas

#8

They are a waste of time and effort.

Even the 4 1/2" diameter ones only provide 3 square inches of NFVA per mini-louver vent. (See www.Lomanco.com/ProductPAGES/CirkVents.html

If you had that much of an overhang, then a continuous strip vent 3" wide would give you 9 square inches per foot, but it sounds like that is not the case.

Yes, rows of shingles can be removed to retro-fit the Smart Vent in place and then re-installed.

Ed