As per the title really.

Shed newbie 🙂 Current (decent) shed bought from new and knocking on for five years old. The roofing felt is a mineral-faced polyester type, installed with clout nails.

The felt looks OK from the outside to my untrained eye, but recently I’ve noticed that the shed is generally quite damp. Poking around inside today the roof is damp to the touch.

The only other option I can think of is an overload of moisture inside. Bikes quite often go away relatively wet, and don’t dry out especially quickly, particularly at this time of year.

Is it worth drilling some holes in the eaves areas to try to encourage airflow to dry things out, or does it sound like time to replace the felt?

If the felt was leaking you’d see water coming in and staining the timber, surely? It has to be condensation, especially if a bit of winter sun hits the shed, warms it up a bit and the resulting humidity hits cold surfaces. The clue is in you saying the bikes don’t dry out very well. Watch for rust if they salt the roads as the salt will grab moisture.

Very likely condensation but mine can leak in where the clout nails make a hole. I give them a slosh with roof repair every year or so. When the roof repair cracks another blob cures it for a bit …. I keep on meaning to recover with the fancy rubber stuff but I’d rather ride my bike.:-)

Thanks folks.

Looks like ventilation holes FTW, then.

Refelt sheds for a job, is the felt looking tatty,is it overlapped by about a 1/3 or half sheet, is the felt overlapped from top of apex to base of slope, seen sheds felted the wrong way so water runs down under felt.
Give it a few coats of roof seal with a paint roller, pour on at top of apex and roll out, on a dry day.

As for condensation, fit some hit and mis ventilators at base and near top of apex https://www.toolstation.com/hit-miss-vent/p95380

Thanks @project.

No, the felt isn’t looking tatty at all. It is overlapped as you say, about 1/3 sheet, from apex to base 🙂 so water shouldn’t run under the felt.

I’ll give the roof seal a look!