Abstract: Clay tiles are the most common roof covering in Italian buildings, in particular in traditional residential buildings. Given the important role of the roof characteristics for building energy efficiency and indoor thermal comfort conditions, innovative solutions for improving the thermal-energy performance of such diffused roof element has become a key research issue. In this view, cool roof applications represent an effective solution to this aim. The present work deals with the analysis of innovative coatings for traditional clay tiles, aimed at increasing their “cooling” potential. Several pigments with the sodium silicate as binder are tested in terms of reflectance and emittance, which mainly determine the cool roof performance. Additionally, the year-round performance of the proposed tile is evaluated when applied to a single family residential building located in central Italy. The developed cool roof solution is characterized by the same visual appearance of traditional “natural brick” color tiles, while the solar reflectance is higher than natural terracotta tile by 13%. Therefore its thermal performance is optimized in order to reduce the roof overheating and the consequent energy requirement for cooling. Results of dynamic simulation of the case study building show how the proposed tile is able to decrease the number of hours when the indoor operative temperature of the attic is higher than 26°C by 18%, while the same effect in lowering the indoor temperature below 20°C in winter is less than 1%. Therefore, the proposed solution could be considered as an interesting strategy for new buildings or for traditional roof retrofitting, without producing any significant architectural impact, even in traditional or historic buildings, where more invasive solutions are too difficult to be implemented. © 2013 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of ATI NAZIONALE.

Abstract: This article reports an analytical study of natural convection in a wedge-shaped horizontal space filled with a fluid-saturated porous medium. The study focuses on the detrimental effect of natural convection on the insulation value of an attic-shaped porous layer in "winter" conditions (cold roof, warm ceiling). The study reveals the most basic features of the temperature field and flow pattern established in the porous layer. The study addresses two distinct flow regimes: (a) the shallow attic limit (H/L—0, Ra

Abstract: Problems with high humidity levels and mould growth in cold attics have been increasing over the last few years. A recent Swedish study showed that as many as up to 60 – 80 % of the single-family houses in Vastra Gotaland (largely, the Gothenburg region) are showing significant mould growth and thereby risk developing serious moisture problems. The high humidity levels are to a large extent a consequence of the increasing demand on energy efficiency. Houses are frequently retrofitted with additional attic insulation, which leads to a colder attic space and hence a higher humidity. Furthermore, furnace heating is often replaced in favour of heat pumps or district heat. This may alter the air-pressure balance of the house, resulting in an increased thermal pressure on the ceiling with subsequent air-leakage up to the attic. Also newly built attics have problems. A risk assessment of the risk for mould growth is performed for different design of the attic. Also a simplified life cycle cost is estimated for the different design alternatives. The alternative with controlled ventilation is estimated to be risk free with lowest life cycle cost. Roof insulation gives low risk for mould growth in northern part of Sweden.

Abstract: The fire dynamics simulator (FDS) fire model, which is developed and maintained by the National Institute of Standards and Technology (NIST), was used to provide insight into the dynamics of a fire that occurred on November 2, 2012, within a 2 ½ story, single family structure in Chicago, IL, that resulted in the death of the captain of a fire department. The inputs for the FDS simulations are documented in this report and are based on the fire scenario, including the building geometry, interior furnishings, and ventilation conditions. The fire started in the attic and spread down through an opening into the enclosed porch on the rear of the structure. This resulted in ventilation limited (fuel rich) fire conditions in the attic and rear porch areas. Further spread of fire and hot gases from the attic downward into the second floor of the structure was limited by a closed steel-faced, wood-framed door. Note that there was no evidence of fire damage on the first floor of the structure. After exposure to the elevated temperatures and pressure from the fire in the porch area, the wood frame of the door decomposed, the steel faces of the door failed, and the door collapsed inward. The door failure resulted in the establishment of a flow path between the higher pressure and higher temperature conditions in the enclosed porch and the lower pressure and lower temperature conditions in the hallway and kitchen areas of the second floor. The temperature of the gases that flowed into the hallway exceeded 260°C (500°F) at a height of 1.86 m (6 ft). Unfortunately, a captain and firefighter were advancing a hose line in the hallway near the door at the time of the door failure. It appears that the captain was likely overcome by the rapid change in conditions before he could exit to the safety of the kitchen area. After a Mayday call, the captain was rescued from the structure, but later succumbed to his injuries.

Abstract: In African hot tropical climate countries, due to climate and the unsuitability of construction materials, building’s indoor environment remains over the thermal comfort acceptable limit over long periods of time during the year. Among the building envelope components, roof is a critical part that is highly susceptible to solar radiation. Solutions like passive cooling and low energy consumption systems are not explored enough in those countries. These techniques and systems can be used to meet a large part of the cooling needs and reduce the overheating period in buildings, but their applicability depends on the climate zone. In this paper, investigations were conducted to determine their potential to improve steel roof performance for free running buildings under tropical climatic conditions. The case studies are two configurations (with and without attic) of typical steel roof in Burkina Faso. Using dynamic simulation, we have evaluated the impacts of radiant barrier, insulation, cool paint and ventilation for two configuration of roofing. For both configurations, high reflective solutions perform very well. It also appears that the attic case due to its actual configuration (shape and design) and to the climate conditions ventilation does not perform very well. These results can help building actors during the design process.

Abstract: Abstract The evaluation of daylight conditions in building interiors is based on the Daylight Factor concept after current Slovak standards. Criteria and requirements determined in these standards consider the worst daylight exterior conditions which are described by CIE overcast sky model. The sky luminance distribution of overcast sky is centrical to the zenith, so independence of window orientation to cardinal points is characteristic in daylighting calculations. The sky luminance distribution modelling is one of the main task of the daylight source research more than 50 years. It is evident that also other types of sky conditions exist in nature. An introduction of a new criterion based on photometric variables, which also consider sunlight influence, is expected. This article represents a study of the influence of the interior orientation on distribution of daylighting in attic spaces under an overcast and clear sky

Abstract: This paper investigates the thermal performances and heat gain reduction of a new roof tile design referred as Ventilated Roof Tile (VRT) compared with an ordinary corrugated concrete roof tiles (CCR). The outside dimension of each small house was 1.70 x 1.70 x 2.85 m3 (W x L x H) and inside dimension was 1.50 x 1.50 x 2.20 m3. The volume of each room was 4.95 m3. The gable roofs slope were 25o and surface area of VRT was 2.58 m2 per each side facing north and south. The VRT tile composed of upper cement plate 40 × 40 cm2 and lower cement plate 30 x 40 cm2. Between plates was 3 cm thickness air gap. The experimental results showed that the top surface of VRT was lower than CCR about 2.10°C for average temperature (from 6:00 18:00) and made VRT room temperature lower than CCR about 1.41°C for average temperature. VRT could reduce heat gain with air flow rate through the roof tiles gaps varied following the solar radiation, during time 8:00-17:00 the natural ventilation varied from 0.003-0.014 m3/s (10.6-50.0 m3/hr.). Observed that, during 17:00-18:00, the air flow rate is about 0.003 m3/s (10.8 m3/hr.) due to heat accumulated in the attic space and roof tiles.

Abstract: Widespread damage to residential roofing systems during Hurricane Andrew in 1992 highlighted the structural inadequacy of wood roof sheathing attachment in existing Florida homes. Prior research found that retrofitting wood decks with closed-cell spray-applied polyurethane foam (ccSPF) could provide adequate wind resistance to pre-1994 roofs. However, it is unknown whether this retrofit method increases the potential for moisture to accumulate in the roof sheathing, and if so, what effect this has on the strength of the bond between the ccSPF and the wood substrate. Five full-scale roofs were subjected to natural weathering for 3 months, and 131 small-scale laboratory samples of ccSPF bonded to wood sheathing were intermittently sprayed with water and stored in a high-humidity environment for up to 16 weeks. These tests enabled systematic assessment of the effects of water leakage on ccSPF-retrofitted roof structures. The attic roofs were retrofitted with two ccSPF configurations and covered with ...

Abstract: The fire dynamics simulator (FDS) fire model, which is developed and maintained by the National Institute of Standards and Technology (NIST), was used to provide insight into the dynamics of a fire that occurred on November 2, 2012, within a 2 ½ story, single family structure in Chicago, IL, that resulted in the death of the captain of a fire department. The inputs for the FDS simulations are documented in this report and are based on the fire scenario, including the building geometry, interior furnishings, and ventilation conditions. The fire started in the attic and spread down through an opening into the enclosed porch on the rear of the structure. This resulted in ventilation limited (fuel rich) fire conditions in the attic and rear porch areas. Further spread of fire and hot gases from the attic downward into the second floor of the structure was limited by a closed steel-faced, wood-framed door. Note that there was no evidence of fire damage on the first floor of the structure. After exposure to the elevated temperatures and pressure from the fire in the porch area, the wood frame of the door decomposed, the steel faces of the door failed, and the door collapsed inward. The door failure resulted in the establishment of a flow path between the higher pressure and higher temperature conditions in the enclosed porch and the lower pressure and lower temperature conditions in the hallway and kitchen areas of the second floor. The temperature of the gases that flowed into the hallway exceeded 260°C (500°F) at a height of 1.86 m (6 ft). Unfortunately, a captain and firefighter were advancing a hose line in the hallway near the door at the time of the door failure. It appears that the captain was likely overcome by the rapid change in conditions before he could exit to the safety of the kitchen area. After a Mayday call, the captain was rescued from the structure, but later succumbed to his injuries.

Abstract: The objective of this study is to examine the reduction in heating and cooling loads that may be attributed to the use of attic radiant barrier and to identify environmental parameters that influence this reduction. To this end, an experimental study was conducted in Zachary, Louisiana for 8 months on two houses built in the same manner and instrumented with thermocouples to measure the temperature in each hour and each layer of the roof. Results showed that an attic radiant barrier can reduce energy loads from 8% to 25% depending on the climatic conditions. Among the evaluated climatic parameters, ambient air temperature had the greatest effect on the ceiling heat flux.

Abstract: A closet or enclosure 100 (closet) fit into an attic. A panel ( 110 ) forms the bottom of the closet. The panel can be lowered to the living space below manually or by using a return spring or electrical means. The panel holds a cabinet, box, or other storage item ( 105 or 2225 ). Air space ( 150 ) around the cabinet or items insulates it from thermal contact with the walls. Alternatively a cabinet is hung from a restraining member ( 145 ), or arm ( 1105 ), so it can be raised for storage and lowered for access. In this aspect, the panel is secured to the bottom of the cabinet. Optional vents ( 155 ) and fan ( 160 ) urge circulation between the air space and the living space, reducing temperature extremes in the air space and hence the cabinet. In other aspects, air treatment units (HVAC, dehumidifier, etc.) condition the air within the closet or enclosure.

Abstract: BACKGROUND AND PURPOSE: An acquired attic cholesteatoma may spontaneously drain externally into the external auditory canal, leaving a cavity in the attic with the shape of the original cholesteatoma but now filled with air, a phenomenon referred to as “nature9s atticotomy” or auto-atticotomy. We describe and quantify the CT appearance of the auto-atticotomy cavity as it pertains to the appearance of the scutum and the lateral attic wall. MATERIALS AND METHODS: Twenty-one patients with erosion of the scutum and loss of the lower attic wall on MDCT were identified during a 5-year span. Images were assessed for measureable widening of the space between the ossicles and the lower lateral attic wall in the axial and coronal planes. Three measurements of the lateral attic were made on the axial images. Findings were compared with the same measurements in 20 control subjects. RESULTS: The 21 patients had a characteristic blunting of the scutum with loss of the lower lateral attic wall and widening of the lateral attic, consistent with an auto-atticotomy. There was a statistically significant (P CONCLUSIONS: Spontaneously evacuated cholesteatoma may mimic a surgical atticotomy on MDCT. Scutal erosion and attic enlargement with a smoothly contoured bony remodeling of the lower lateral attic wall in a patient with no history of surgery suggest that a cholesteatoma was previously present and spontaneously drained.

Abstract: The following article deals with the problem of icicles formation on the roofs and the elimination methods. The attic roofs with pitched roofing are highly susceptible to this negative phenomenon.In work warming of garret overlappings as a method of prevention of formation ice-dams on roofs of buildings in the operation, being characterized is in detail considered by the lowest temperatures of external air.

Abstract: An insulating system comprises a cover and a generally rigid attic sealing member. The cover defines an interior chamber, and the interior chamber is filled with insulation. The cover further forms a cavity in the bottom of the cover, where the attic sealing member is received into the cavity. Together, the system raises the insulating value (R-value) of an area above an attic opening to a minimum R-value level required by many building codes. The cover may be filled with insulation through a slit or passage extending along the top of the cover.

Abstract: The reality of the effect of natural ventilation in a residential attic cavity has been the topic of many debates and scholarly reports in the field of Residential Building Envelopes since the 1930’s. The purpose of ventilating the attic cavity is to prevent collection of condensate on the structural surfaces and create a thermal buffer between the conditioned space and the ambient air. The current American standards are not specific to climate zone, despite the fact that each climate zone may require ventilation for very different reasons.

Abstract: IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Warme und Feuchte instationar Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

Abstract: An attic stairway insulator assembly configured for placement within a building scuttle is provided. The building scuttle has a length and a width. The attic stairway insulator assembly includes a base configured to cover the building scuttle. The base has a length and a width corresponding generally to the length and the width of the building scuttle. A bag is seated on the base and has insulative material within a jacket. The bag has a length that is longer than the length of the base and a width that is wider than the width of the base such that portions of the bag having the insulative material drape over portions of the base.

Abstract: An affordable “non-surgical” method for retro-upgrading a house to better withstand hurricane winds and rain is described, wherein the winds' most strongly depressurized eddies or “Separation Zones” bordering the building envelope are clearly identified and “harnessed” by assured venting of the interior space just into such, thereby depressurizing the interior likewise and strongly reducing or eliminating any net outward-acting force on the building envelope. The “harnessing” is assured simply by installing one-way valves over the vent openings, whereby air can pass outward from the interior to strongest-depressurized Separation Zones but inward flows (such as on the windward) are quickly blocked by the other valved vents “blowing closed”. The roof envelope surrounding the attic is especially addressed, wherein winds from any direction will strongly depressurize the attic and so help hold the roof sheathing down, gables on, soffits and ceiling up—while the valves also block ruinous rain entry on the windward.

Abstract: The utility model discloses a ventilation building used for animals. Air inside the building and external air well circulate, the appropriate temperature inside the building can be ensured, and therefore growth of animals is facilitated. The ventilation building comprises a closed room which comprises two or more independent partition walls and is used for containing animals, and an attic is arranged on the top of the room. The ground of the room is a leak type floor. An excrement cleaning pool below the leak type floor is connected with an external septic tank through an excrement processing pipeline. The excrement cleaning pool is communicated with the outside world through one or more air ducts. An exhaust fan is arranged on the top of each air duct. The attic is communicated with the outside world through one or more ventilation pipes, and external fresh air enters the attic through the ventilation pipes, enters each room body through the attic and then enters the septic tank and the air ducts, and is finally exhausted through the exhaust fans. Meanwhile, air inside the ventilation pipes can exchange heat with the ground or the septic tank.

Abstract: The Guide to Attic Air Sealing was completed in 2010 and although not in the standard Measure Guideline format, is intended to be a Measure Guideline on Attic Air Sealing. The guide was reviewed during two industry stakeholders meetings held on December 18th, 2009 and January 15th, 2010, and modified based on the comments received. Please do not make comments on the Building America format of this document. The purpose of the Guide to Attic Air Sealing is to provide information and recommendations for the preparation work necessary prior to adding attic insulation. Even though the purpose of this guide is to save energy - health, safety and durability should not be compromised by energy efficiency. Accordingly, combustion safety and ventilation for indoor air quality are addressed first. Durability and attic ventilation then follow. Finally, to maximize energy savings, air sealing is completed prior to insulating. The guide is intended for home remodelers, builders, insulation contractors, mechanical contractors, general contractors who have previously done remodeling and homeowners as a guide to the work that needs to be done.

Abstract: PROBLEM TO BE SOLVED: To provide a high-clean room system capable of maintaining air cleanliness of class 1 or higher at all the time and supplying oxygen enough for a plurality of human beings to live into a room, and a wall appropriate for use in the configuration of the system.SOLUTION: A high-clean room system 10 comprises a habitable space 6 and an attic 5 as partial spaces of a closed space formed by a room 1a. One of sidewalls of the room 1a is formed from a wall 9 which is a hollow wall including an internal space 7. The internal space 7 and the habitable space 6 are in contact via an inner wall 9a of the wall 9, and a gas exchange film 26 is spread over the inner wall 9a. A gas flow passage 24 is provided inside of the internal space 7, and the gas flow passage 24 communicates, with air tightness, an opening 23 provided in a lowest part of the inner wall 9a and a gas inlet of a fan/filter unit 21 provided on a ceiling wall 2a inside of the attic 5.

Abstract: This paper investigates the thermal performance of the tile ventilator for attic ventilation to reduce ceiling heat gain into space room. Two small houses were built using common construction materials; one common house served as reference and the other was used to test in experiments. The external ventilation pattern was considered. The inlet air openings are located at eaves and the outlet air at the tile ventilators. The results were performed that the tile ventilator is effective for reducing attic air temperature, ceiling temperature and also room temperature. Due to solar intensity during daytime, the tile ventilator could decrease heat accumulation in attic space. However, it is suitable for promoting to integrate on the roof tile.