Valved cover for perforated-strip soffit vents

Abstract

A valved cover is described for controlling air flow through perforated-strip-type soffit vents surrounding houses. The narrow, continuous vents are completely enclosed except for valved portholes in the cover, the flap valves being stiffly hinged to stay open (and quiet) in most weather to allow two-way ventilating air flow between outdoors and attic/roof space. The valved covers “harness” very strong winds: those on the the windward have their valves blown closed, blocking potentially destructive wind/rain entry into the attic/roof space, while those facing lee sides remain open so that the attic/roofspace is connected only to the wind-depressurized lee-side air and is therefore itself depressurized, helping hold the roof envelope together. The valved covers can be factory-mounted on the soffit panels and flat-folded for compact shipping and handling.

I claim: 
     
         1 . A valved cover affixed over a perforated strip soffit vent to control air flow through said vent, comprising:
 a cover enclosing an air space over the perforated strip vent, the cover having its side edges affixed to the soffit's upper surface along the long sides of the perforated strip vent;   an end wall closing each end of the cover, each end wall being affixed to the cover and the soffit's upper surface to complete the cover's enclosure of air space over the perforated strip vent;   portholes in at least one side slope of the cover, the portholes offering a total open area similar to the perforated strip vent's open area and so allowing ventilating air flow inward and outward between outdoors and a roof space;   flap valves positioned inboard of the portholes and hinge attached to the cover, the hinging having a certain stiffness holding the flap valves away from the portholes;   whereby in most weather conditions the flap valves remain quiet and leave clear pathway for air flow inwardly or outwardly through the perforated strip vent and through the air space over the perforated strip vent and thence through the portholes to ventilate the roof space, but when subjected to outdoor wind pressures pushing inwardly toward the roof space with a certain strength the flap valves are pushed closed across the portholes, thereby blocking wind and rain entry into the roof space; while at the same time those soffit vents located around the wind-depressurized lee-sides of the house, similarly covered with the valved vent covers, remain open so that the roof space is connected only to the lee-side air so the roof space is itself depressurized, reducing net outward-acting air pressures trying to force apart the roof space envelope.   
     
     
         2 . A valved cover according to  claim 1  comprising:
 a first sidewall having its bottom edge hinge-connected to the soffit along a first side of the perforated strip vent; 
 a top piece extending across much of the width of the perforated strip vent and having a first side edge hinge-connected to the top edge of the first sidewall; 
 a second sidewall having its top edge hinge-connected to the second edge of the top piece and having its bottom edge hinge-connected to the soffit along the second side of the perforated strip vent; 
 portholes in the second sidewall offering a total open area greater than the perforated strip vent's open area, thereby minimizing the net pressure differential that roof space air can exert downward on the valved cover when leeside depressurizations are strong; 
 flap valves hinge-attached to the top piece with the hinging having a certain stiffness; 
 end walls insertable into each end of the valved cover; 
 wherewith the valved cover less its end walls can be folded flat atop the soffit board for compact packaging and shipping to the job site, where before installation on the house the valved cover is raised into its vaulted form enclosing an air space above the perforated strip vent and the end walls are inserted and affixed to support the valved cover's vaulted form and complete its enclosure of the air space. 
 
     
     
         3 . A valved cover according to  claim 2 , wherein:
 the end walls are made of fabric permanently attached to the ends of the valved cover and the soffit thereunder;   a support plate is positioned lengthwise under the valved cover, the plate having one side edge hinge-connected to the cover's underside, the plate's opposite side edge resting unattached atop the perforated vent strip, the plate's width being the desired final height of the valved cover and the plate being generously apertured to allow air to flow freely through it;   stops such as short pegs are affixed along the perforated strip vent under the support plate;   wherewith the complete valved cover can be folded flat atop the soffit board for compact packaging and shipping to the job site, where before installation on the house the valved cover is raised into its vaulted form enclosing an air space above the perforated strip vent, thereby pulling up the hinge-connected side edge of the support plate and dragging forward the support plate's opposite side edge partly across the perforated strip vent and over and just past the stops, the stops then keeping the plate's opposite side edge from slipping backward and so locking the plate into a suitably upright stance to support the valved cover's vaulted form.   
     
     
         4 . A valved cover according to  claim 2  wherein a single fabric piece replaces the first sidewall and the top piece, the fabric piece having a first side edge attached to the soffit along a first side of the perforated strip vent, the fabric piece thence extending across much of the width of the perforated strip vent and being there attached to the topside edge of the opposite sidewall, and the ends of the fabric piece forming the fabric end walls to complete the valved cover attached to the soffit panel to enclose the perforated strip vent, wherewith the complete valved cover can be folded flat atop the soffit board for compact packaging and shipping to the job site, where the valved cover is raised into its vaulted form enclosing an air space above the perforated strip vent, thereby pulling up the hinge-connected side edge of the support plate and dragging forward the support plate's opposite side edge partly across the perforated strip vent and over and just past the stops, the stops then keeping the plate's opposite side edge from slipping backward and so locking the plate into a suitably upright stance to support the valved cover's vaulted form. 
     
     
         5 . A method for improving a house's resistance to damage from hurricane-force winds and rains by controlling air flow through perforated-strip vents of soffit boards enclosing the eaves around the house, comprising steps of:
 providing valved covers for the perforated strip vents, the valved covers having a plurality of portholes therethrough, with a plurality of flap valves operably attached to an inner surface of the cover inboard of and spaced away from the portholes, said flap valves being stiffly hinged to remain open and quiet except when subjected to very strong inward-acting wind pressures which close the flap valves over the portholes to block wind and rain entry therethrough;   affixing the valved covers atop the soff it boards over their perforated strip vents to enclose an airspace bounded by the valved cover and said vent;   folding the valved covers flat atop the soffit boards, thereby allowing compact packaging and shipping to the house;   thence unfolding the valved covers and supporting them in their vaulted form over the perforated strip vents; and   installing the soffit boards integral with the valved covers to enclose the eaves around the house;   whereby the flap valves of the valved covers leave the portholes open in most weather conditions to allow two-way air flow between outdoors and roof space through the perforated strip vents to provide roof space ventilation, but those windward flap valves facing a certain amount of inflow pressure from windstorms are pushed closed over their portholes, that closure blocking wind/rain entry through the soffits' perforated strip vents; while at the same time the valved covers on the lee-side remain open so that the roof space air connects only with the wind-depressurized lee-side air and is therefore itself depressurized, substantially reducing net outward forces induced by wind action on the roof envelope and so helping keep the envelope intact.   
     
     
         6 . A valved cover according  claim 1  formed flexibly to allow flat-folded installation on the perforated strip soffit vent for compact packaging and shipping to a job site, and equipped to be raised and affixed into a vaulted form enclosing an air space above the perforated strip vent.