Abstract: An algorithm was developed for predicting the rates of airflow and heat flow in an inclined air space heated from above or from below. The algorithm yields the mass flow rate and the temperature rise of the thermally induced flow rate. The flow and convective heat transfer are very similar to those occurring in inclined cooling ducts formed by offset roof-mounted photovoltaic installations. The algorithm is useful for predicting the free laminar convection heat transfer prevalent in roofs elevated from the roof deck. The routine was implemented in an attic simulation code and validated against thermal field data for stone-coated metal roofs equipped with above-sheathing ventilation.

Abstract: This thesis examines the use of aerial thermography data to discriminate loft (attic) insulation levels in residential housing, with ventilated pitched roofs, in the UK. Quantitative techniques from the fields of remote sensing, GIS, building physics and atmospheric science were used to develop a methodology and analyse survey data flown over Nottingham in 2001. The quantitative techniques were applied to real survey data using the most up to date atmospheric propagation models. A new model of the heat loss through the ceiling, loft and roof was developed for this study, based on the most recent methods. The limitations of these techniques were explored. A complete methodology, valid for any future study, was defined. It was found that, measuring roof surface temperature from the thermal image was complicated by roof material properties, the intervening atmosphere and the surrounding topography. Relating roof surface temperature to insulation thickness was further complicated by loft space ventilation and the outside surface heat balance. The additional data, needed to quantify the results, produced inaccuracies caused by measurement error. Analysis of the uncertainties, by simulation, indicated that loft insulation level could not be discriminated by aerial thermography. This was confirmed by comparing the results, calculated from the survey data, with the actual insulation level for a number of houses in test areas of the city.

Abstract: A method of sealing an attic access opening; a first step for which involves providing an attic access opening with a peripheral interior sidewall. A second step involves providing an insulated attic access cover, which consists of a first panel having a peripheral edge and a second panel having a peripheral edge. A flexible web connects the peripheral edge of the first panel with the peripheral edge of the second panel, and defines an insulation cavity between the first panel and the second panel filled with compressible insulation. A third step involves positioning the insulated attic access cover within an attic access opening and moving the first panel and the second panel toward each other to compress the insulation in the insulation cavity and cause the insulation to bulge outwardly to engage the peripheral interior sidewall of the attic access opening.

Abstract: This article addresses the buoyant air circulation inside attic spaces of houses and buildings with sloped roofs and horizontally suspended ceilings. In order to counteract the excessive heat transmission through the roof that takes place during the wintertime, when the attic is heated at the base, this study attached an array of baffles onto the top inclined walls to alter the flow characteristics of the buoyant air. To perform the computational analysis, the finite volume method is the vehicle for the discretization of the conservation equations. The Boussinesq approximation is not invoked, and all thermophysical properties are considered as temperature-dependent. Simulations are performed for several values of baffles length and the Rayleigh number. The influence of these parameters upon the flow and temperature patterns is analyzed and discussed. A comparison of the thermal performance between baffled attics and non-baffled attics is presented. The results show that the presence of baffles provides an...

Abstract: Airtightness of the building envelope is a key factor for good performance of a building. The main part of this thesis deals with the exploration of a transient pressurisation method for air leakage measurements. In the transient method, an enclosure is pressurised to a desired pressure. The air flow into the enclosure is then stopped. The pressure starts to decline due to air leakage through the walls of the enclosure. The pressure decline is measured. The air leakage rate, as a function of the excess pressure, is obtained from a formula that involves the time derivative of the pressure. The formula also involves air heat capacity, potential volume change due to excess pressure, and heat exchange between air and enclosure. The main benefit of the method, compared to the static method, is that it eliminates the need of airflow meters. It also gives a continuous relation between pressure and air leakage rate. The method is validated against the common static method, and against empirical values of air leakage through sharp-edged openings. The agreement is very good. The development of the method involves studies and analysis of curve fitting, volume change, heat flux, and oscillations due to inertia of the airflow. The particular complication of an unknown volume change is overcome by performing two measurements, one without and one with an added opening with known leakage. The method is applied to cases of air leakage through a wood frame wall, an attic floor and a knee wall construction. The measurements are performed in a laboratory environment. The results from these measurements show that the method can be used also in cases of large and non-linear volume change of the enclosure. Transient opening and closing of leakage paths may be detected. The testing of the building components also show that it is quite easy to make these components sufficiently airtight, with moderate efforts only. The method is also applied to air leakage through well-defined leakage paths. Air leakage through these paths is also simulated with a CFD-tool. Simulations and measurements show in most cases very good agreement. In cases involving porous materials, even a small void in the insulation near an inlet or outlet opening may have a large impact on the air leakage rate. A second part of the thesis deals with modelling of air leakage in a single-family house. The modelling shows that the ventilation system has a large impact on the result. The models also show that wind is a mitigating factor, in most cases, regarding transport of indoor air to the attic. In cases of indoor air transport to the attic it is necessary to ventilate the attic. In a climate similar to the one in Gothenburg, ventilation of an attic can, however, cause moisture problems. There is a delicate balance between providing sufficient ventilation of the attic and too much ventilation.

Abstract: An insulation product having an integral air vent channel is disclosed for use in attic and cathedral ceiling applications. The product includes an insulation blanket having at least a pair of raised strips formed on one side thereof. When installed, the blanket is fit up between a pair of roof rafters until the raised strips contact the undersurface of the roof. The strips ensure that a predetermined offset exists between the insulation blanket and the roof, thus forming an unobstructed ventilation path running from the soffit to the roof peak. The raised strips can be foamed polyurethane or other polymer material that is dispensed or laminated onto the insulation blanket after the blanket exits the curing oven. The blanket may be a foamed polymer insulation that is extruded as a blanket at the proper insulation height for installation or may be cut to size from an overthick bun of insulation. The blanket and strips may be formed by a mold that shapes a pour in place foam. The blanket, with attached strips, can then be compressed for packaging and shipping. When unpackaged at the work site, the insulation product can be installed between roof rafters without the need for a separate vent panel, thus simplifying the installation process.

Abstract: There is provided a ridge ventilation system that comprises a ridge slot disposed longitudinally in a ridge of a roof and a fan disposed in the ridge slot for actively exhausting air from an attic substantially enclosed by the roof, sidewalls and ceiling into the ambient atmosphere. There is further provided a method for ventilating that comprises disposing a ridge slot longitudinally in a ridge of the roof and operating a fan disposed in the ridge slot to actively exhaust air from the attic into the ambient atmosphere. Lastly, there is provided a method for installing the ridge ventilation system that comprises constructing a ridge slot longitudinally disposed in a ridge of the roof and disposing a fan in the ridge slot to actively exhaust air from the attic into the ambient atmosphere.

Abstract: The assessment of the thermal performance was carried out on a low cost house mainly built from waste oil palm shell (OPS-Concrete) with galvanized steel-roof It was noticed that reasonable thermal comfort took place during the night for the roof without ceiling and without insulation, and during the day at a peak temperature of a highly ventilated attic area For such situation, it was recommended to install insulating horizontal plated surface under the roof, which should be turned into a vertical position during the night Other alternatives may be creating small adjustable openings around building envelope just under the ceiling or making an open roof-ceiling system This technique will reduce the heat flux from insulated ceiling by the flow of the cooling air at night, but the impact of surrounding microclimate on human thermal comfort should be considered The mathematical model used to predict the attic temperature for a lightweight roof system was obtained by correlation, which can be used for a quick inspection Insulation materials of 50 mm fibreglass and foil-aluminium were used with sealed attic, and found the ceiling temperature reduced by about 3 oC and 2 oC respectively For the case of fibreglass of thickness beyond 50 mm, the reduction of ceiling temperature was recorded less than ½ oC, really not attractive Keywords: thermal performance, metal roofing, attic temperature, sealed attic, ventilated attic, insulation

Abstract: PROBLEM TO BE SOLVED: To improve air conditioning efficiency in a simple constitution in the structure of a computer lab. SOLUTION: This structure of a computer lab S which is partitioned into three layers of an attic S 1 , a room S 2 and an underfloor space S 3 by a suspended ceiling 6 and a double flooring 7 and whose air is conditioned using outside air introduced from the outdoor space and air circulating in the indoor space, is provided with an outside air intake damper 3 interposed on a circulation passage for circulating the outside air from the outdoor space to the attic S 1 and controlling the flow rate of the outside air, an exhaust shutter 8 interposed on a circulation passage of exhaust exhausted from the indoor space to the outdoor space and controlling the flow rate of the exhaust, and an air conditioning indoor unit 5 for executing a blowing operation for blowing the outside air from the attic S 1 to the room S 2 via the underfloor space S 3 , and a cooling operation for supplying cooled air from the attic S 1 to the room S 2 via the underfloor space S 3 . COPYRIGHT: (C)2009,JPO&INPIT

Abstract: We consider the heat transfer through the attics of buildings under realistic (periodic) thermal forcing. The objective of this study is to investigate numerically the effect of the aspect ratio (height to base ratio) on the heat transfer through the attics. A fixed Grashof number $1.33\times 10^6$ is considered for three different aspect ratios~0.2, 0.5 and~1.0. The Prandtl number is also fixed at~0.71 for air. The details of the numerical model as well as the flow structures and heat transfer data are presented.

Abstract: PROBLEM TO BE SOLVED: To provide a solar system capable of realizing effective heating by preventing upward radiation of heat collected under a floor by a draft in a downward duct, capable of effectively using auxiliary heating, and capable of positively realizing heating in not only the first floor but also in a room of the second floor, in regard to a solar system house sending air subjected to heat collection directly below a roof face to an underfloor space by a downward duct via a handling box provided with a damper and a fan installed in an attic space being a space under the roof SOLUTION: A second handling box 24 is provided on a lower end of the downward duct 10, an air outlet 25 to the underfloor space and an air outlet 26 to a room are formed on the second handling box 24, and a damper 27 is provided for selectively opening and closing the two air outlets COPYRIGHT: (C)2008,JPO&INPIT

Abstract: Dormers have found wide applications in the design of new buildings and also in the renovation of under-roof spaces in existing buildings. Comfort and illuminance for visual activity in attic rooms illuminated by dormers depends mainly on the dormer dimensions and its position with respect of the utilization area of the room. This article evaluates selected types of dormers for daylighting of attic rooms. The evaluation of daylighting from dormers in the administrative part of the university building was carried out using computer simulations and illuminance measurements. The daylighting studies were completed for separated dormers compared with the alternative design solution of one continuous dormer with the same glazed area. Results from computer simulations give information about illuminance level and daylight distribution in the whole area of the investigated rooms. Daylighting simulations for the dormer were compared with alternative design solution with skylights.

Abstract: This paper deals with a common moisture problem in Swedish houses – the occurrence of high moisture levels in attics, and with a remedy proposed by building authorities – the ventilation of attic by outdoor air. The aim of the work is to identify operating scenarios for an attic that lead to a moisture accumulation on internal side of the roof and to investigate whether ventilation (governed by wind) may help in removing the moisture excess. The role of the attic ventilation is analyzed by comparing attics with different air infiltration rates from a dwelling. The investigation aims to exemplify that, by using advanced simulations, a number of sound conclusions can be made by these virtual experiments in a rather easy and inexpensive way.

Abstract: PROBLEM TO BE SOLVED: To add an air circulation structure for raising air conditioning efficiency of a building after an extension building is constructed, and enhance interior comfort and energy saving of the extension building. SOLUTION: The extension building is constructed by removing a roof member from an existing building, installing a new wall member and a roof member to surround the outer circumference and the top of the existing building, the new wall member is extended from the existing building to a story extended above the existing building, a new floor member is installed on the ceiling member of the uppermost story of the existing building and a living space is formed between the new floor member and the new roof member. The side wall of the existing building comprises an indoor side wall substrate and a finishing board remaining after the exterior wall material and heat insulation material are removed. The new wall member comprises an exterior wall material and a heat insulation material disposed opposite to the wall substrate and the substrate board. A ventilation space is formed between the side wall of the existing building and the new wall material and between the ceiling member and the new floor member. A circulation unit for circulating hot/cold air to the ventilation space is installed in an attic space formed by the new roof member. COPYRIGHT: (C)2008,JPO&INPIT

Abstract: The present invention provides a covering for a roof or other surface. The cover reflects solar radiation most notably heat, away from the roof to reduce heat buildup in the attic and in homes or other structures. The reduction of heat will in turn reduce the amount of energy required to cool the home or building structure during the hot summer months. The covering system can be comprised of one or more sections and can be white, light colored, metalized, or be painted or printed with a reflective metallic finish or a combination of finishes. The cover is placed over the roof with the white, light colored or reflective metallic surface facing the sky. The cover also contains slits so that the cover can vent winds that could put excessive stress on the cover or the roof structure. One or more covers can be used on a roof depending on the size of the roof and number of sections. The cover may also be cut or sections can remain uncovered to expose air and plumbing vents, attic fans, chimneys, sky lights, dormers, solar panels, and the like. The cover can be retracted or removed for the cold winter months so that the building structure or home can be warmed by the sun and aide in the reduction of energy used for heating their interiors.

Abstract: A heat exchange system is disclosed herein. In one embodiment, the heat exchange system includes at least one tube having an input end associated and an output end, each associated with a body of water. A portion of the tube has an oval cross-section, and is disposed in a roof or attic space of a structure where warm air in the attic space causes the water in the tube to heat.

Abstract: System and method for providing a roof ventilation system are disclosed. The roof ventilation system may include a core, a filter, and a spanner. The core may be configured to conform to a roof surface irregularity. The filter may be configured to hinder rain and debris from entering into an attic from ambient yet allow air to flow from the attic to ambient. The spanner may be configured to allow the roof ventilation system of adjust for roof slopes.

Abstract: Novel stowed staircases for attics and the like that exhibit highly effective fireproof properties are provided. The combination of sheet metal well sides with ceramic paper covering, a combination thermal board and cement-like construction door, coupled with a sealed gasket at the interface of the stair bottom with the ceiling provide the necessary long-term fireproof capabilities as well as facilitation in installation as a sufficiently lightweight article. In such a manner, the inventive stairway construction may be easily incorporated within a residential or other type unit to aid in the simultaneous accessibility to an attic (or like location) and ability to prevent fire from easily spreading into or out of said attic via the stair assembly itself.

Abstract: Fuel use constitutes a large percentage of the energy costs incurred by growers during winter flocks and increasing fuel costs have illustrated the need for alternative methods to reduce energy usage in broiler production. The objective of this study was to determine the feasibility of using the attic space of a broiler house as a source of pre-heated air to reduce energy usage during winter flocks. A series of air inlets were installed in the ceiling of a broiler house to supply pre-heated air during brooding. Inlets were installed in the peak of the ceiling and manually controlled with a curtain actuator. Temperature and relative humidity data were collected for the brood chamber, attic space, and outdoors. Heater, brooder, and fan run times were also monitored. Heating system run time was reduced for the house with the attic inlet system installed, with estimated gas savings of 128.8 l of LP gas over the first two weeks of a spring flock. Humidity was also reduced in the house with the system installed; the humidity ratio with the system installed was 0.0141 kg water / kg dry air versus 0.0155 kg water / kg dry air in a house with a traditional sidewall inlet system.

Abstract: PROBLEM TO BE SOLVED: To save a space, reduce atmosphere of everyday life and allow the elderly and the disabled to use an attic storage by electrically raising/lowering the attic storage. SOLUTION: This electric storage unit under the roof is so formed that a winding shaft 5 linked with a motor is rotated, a belt 7 is vertically moved synchronously therewith, and a storage 2 is vertically moved with its level retained. This electric storage unit under the roof is provided with guide rings 8, guide rails, a guide plate, and guide rollers. COPYRIGHT: (C)2007,JPO&INPIT

Abstract: An apparatus for applying a shredded foil radiant barrier on top of existing attic insulation. The foil is spun in an air vortex created in a tank, and is blown from there via a hose/applicator to a remote attic. A conical component in the tank helps to establish and maintain the vortex, and to minimize leaving shredded foil in the bottom of the tank.

Abstract: A method of reducing the amount of cooling energy required to cool a building is provided. The method includes disposing a porous insulating material substantially covering the ceiling in the attic space of the building to a substantial depth. The porous insulating material includes a desiccant. The method further includes permitting the desiccant-bearing porous insulating material to adsorb water moisture from the attic space and then permitting the adsorbed water moisture to desorb from the desiccant-bearing porous insulating material into the enclosed room of the building, whereby the temperature of the desiccant-bearing porous insulating material is reduced, resulting in a reduction in the amount of cooling energy required to cool the building.

Abstract: Temperature histories for various types of roof shingles, wood roof sheathing, rafters, and nonventilated attics were monitored in outdoor attic structures using simulated North American light-framed construction. In this paper, 3-year thermal load histories for wood-based composite roof sheathing, wood rafters, and attics under western redcedar (WRC) shingles, wood-thermoplastic composite (WTPC) shingles, and black and white fiberglass shingles are reported and analyzed. The maximum hourly-average temperatures experienced were 70.7 °C and 61.8 °C for black and white fiberglass shingles, respectively; 48.2 °C for WRC shingles; and 45.7 °C and 46.3 °C for WTPC shingles applied over lath or directly over felt, respectively. On hot summer days, black fiberglass shingles were commonly found to be almost 10 °C hotter than white fiberglass shingles and more than 20 °C hotter than WRC or WTPC shingles. Other components in the roof assemblies and the attic air temperatures followed similar trends. The implications of these thermal loads under different types of roof shingles on comparative service-life for the shingles and the various wood components in the roof systems are discussed.

Abstract: SUMMARY Full-scale laboratory measurements were conducted to determine moisture convection performance on the joint of external wall and attic floor. According to field measurements in previous studies this joint is one of the most typical air leakage paths. On this joint also the highest air pressure difference forms in winter. Two commonly used external walls: timberframe and autoclaved aerated concrete walls were measured. The attic floor was in both cases a timber-frame structure. Results from the first laboratory measurement series showed that in leaky joint the moisture convection due to positive air pressure remarkable raised moisture accumulation rate on the inner surface of sheathing. A two-dimensional heat, air, and moisture transport computer model was validated for future analysis. The simulation results showed that CHAMPS-BES program is useful tool in assessing the moisture behaviour of building components including moisture convection.

Abstract: PROBLEM TO BE SOLVED: To improve air conditioning efficiency in a simple constitution in an indoor cooling method. SOLUTION: This indoor cooling method for cooling a room S, which is partitioned into three layers of an attic S 1 , a room S 2 and an underfloor space S 3 by a suspended ceiling 6 and a double flooring 7, using outside air introduced from the outdoor space and air circulating in the indoor space, is characterized in selectively executing either of a first step or a second step according to an outdoor air temperature. In the first step (steps A30-50), the outside air is introduced into the room S 2 using the attic S 1 and the underfloor space S 3 as a ventilation duct and exhausts the indoor air to the outdoor space. In the second step (steps A60-80), the air in the room S 2 is circulated using the attic S 1 and the underfloor space S 3 as the ventilation duct. COPYRIGHT: (C)2009,JPO&INPIT

Abstract: PROBLEM TO BE SOLVED: To provide a heat insulation structure of a roof easy in construction for forming a comfortable space by restraining a temperature change in an attic space while providing the superior heat insulation effect. SOLUTION: This heat insulation structure of the roof is constituted so that a cross-sectional I-shaped rafter 2 composed of upper-lower flanges 21 and 22 and a web 23 is respectively arranged in a plurality on both side of a ridge beam 1; a heat insulation board 3 is arranged between the webs 23 and 23 of the rafters 2 and 2 on both sides of the ridge beam 1 in a state of placing its both end parts 31 and 31 on the lower flange 22 of the rafter 2; a heat insulation material 34 of a small cross section is arranged between end parts 32 and 32 of the heat insulation board 3 of a part of the ridge beam 1; a heat insulation layer is formed for continuing over the other side from one side of the ridge beam 1; a ventilation layer 5 is formed between the heat insulation board 3 and a sheathing roof board 4 on the upper flange 1; and the ventilation layers 5 on both sides of the ridge beam 1 communicate with a ridge part ventilation structure 9 arranged in the part of the ridge beam 1. COPYRIGHT: (C)2007,JPO&INPIT