Balanced roof ventilation is crucial to regulating attic temperature and eliminating mildew year round. A balanced ventilation system typically features intake vents placed near your soffit or fascia and exhaust vents located on or near your roof’s ridgeline.
The system utilizes stack effect and wind to circulate air in your attic space, helping prevent ice dams during wintertime and decreasing cooling energy usage in summer months. Furthermore, proper ventilation prevents the build-up of condensation, reduces energy costs associated with cooling energy usage in general, as well as protecting against mold growth in attic spaces.
Under-ventilated attics can become very hot. Your air conditioner might have to work overtime in an attempt to cool rooms above because the heat from your attic is not being properly dispelled.
Balanced attic ventilation can seem counter-intuitive at first, with its emphasis on adding insulation for warmth while simultaneously building vents to allow cold air in. But balanced ventilation is the key to energy conservation and roof health – as natural air circulation in winter prevents ice damming (when melting snow re-freezes at gutter level).
Your attic ventilation system should include both intake and exhaust vents; intake vents should be installed in the soffit, and exhaust vents in gable or ridge areas of your home for maximum effectiveness in eliminating heat that rises from living areas below. These two elements work in concert with ridge caps to keep both roof and attic healthy by venting away excess heat that rises up from within living areas below.
Moisture build-up in an attic space can be a serious nuisance for homeowners, leading to mold, mildew and wood rot growth – not to mention increased heating bills and air conditioning expenses.
Moisture issues often signal attic ventilation problems. Condensation occurs when warm, moist air from inside the house passes through penetrations in the attic – such as light fixtures, wires, vent pipes or chimneys – and comes in contact with cold surfaces, leading to condensation that forms and condenses onto them. This condensation produces musty or moldy smells which may even reach living spaces below.
Improvement of attic insulation and ventilation can solve this moisture problem, while routing bathroom and dryer vents outside is also essential in avoiding attic condensation. Intake ventilation through soffit vents acts like a bouncer to force hot, humid air out of the attic – providing both upwards and downward air movement through gable or ridge vents as well as intake vents in the soffit of your home.
Ice dams are one of the primary consequences of improper ventilation in an attic, occurring when heated air escapes through ceiling ventilation, warming a section of roofline and causing snow to melt. As this melting snow encounters cold eave and gutter sections, it refreezes, refreezes again, refreezes again until finally blocking flow above it; eventually leading to water backing up behind an ice dam that eventually blocks it and seeping back through into shingles, insulation or walls behind it, potentially leading to wood rot or mold growth if left alone.
Add ventilation to your attic in order to prevent the formation of ice dams and caulk or insulate gaps around attic access hatches, chimneys, plumbing vents and other ceiling penetrations. Finally, redirecting bathroom, kitchen and dryer exhaust vents away from the attic may also help minimize heat leakage into it.
Damage to Roofing Materials
In summer, insufficient attic ventilation allows heat to accumulate to temperatures as high as 160 degrees on some hot days – creating an atmosphere in the attic which can quickly wear away shingles and ruin insulation, leading to premature degradation and damage of roofing material and insulation. This extreme heat can prematurely deteriorate shingles while damaging insulation.
Allowing this heat into living spaces causes air conditioners and other appliances to work harder, leading to higher energy bills and possibly warping wood framing or peeling paint or wallpaper.
Poor attic ventilation can also contribute to ice dam formation in winter months. Ice dams form when heat from inside an attic combines with sunlight outside to melt snow on roof, only for it to refreeze again before reaching gutters and eaves – creating a cycle that results in leaks, rot, fascia boards rotting away, ripping off shingles off and even rusting metal components such as venting duct straps. Opening intake vents is one way of avoiding this scenario.