JP6989837B2 - Strengthen attic insulation without ventilating the attic of the house. In addition, as an integrated heat insulating layer including snow on the roof, it is a construction method that enhances the heat insulation of the roof part and discharges moisture and heat by means of PVC pipes that pass from the attic to the roof. - Google Patents

Description

Building method related to heat insulation of the roof of a house

In the past, we had not considered incorporating snow on the roof into heat insulation. As shown in Fig. 1, the measures taken into the roof are roof 1, wall 2. The attic was ventilated by providing a ventilation port 11 in the ceiling surrounded by the ceiling 15 and taking in the outside air 12 into the attic and discharging it from the ventilation port on the leeward side.
By introducing "attic ventilation", that is, cold outside air 12 into the attic, the temperatures of the attic and the outside air are made more approximate to prevent dew condensation on the attic. The top of the attic heat insulating material glass wool 10 has been treated as a place similar to the outside air. I wasn't thinking about the use of snow cover 13.
Despite the reality that attic ventilation significantly deteriorates the heat insulating effect and causes the room temperature of the living space to drop, the technical problem that dew condensation occurs if attic ventilation is not performed has been well known. , The attic could not be sealed.
Also in the summer, the attic is ventilated, but since the outside air is taken in from the gable board as a ventilation port, the air flow moves from the bottom to the top or in the horizontal direction, so the hot air collects on the upper part of the roof. It could not be discharged downward. This caused the room temperature of the living space to rise, leading to deterioration of the living environment.

In the construction method of the prior art, attic ventilation 12 is performed as shown in FIG. 3 in order to prevent dew condensation on the attic. Cold air (winter) is circulated in contact with the upper surface of the heat insulating material glass wool 10 on the ceiling. For this reason, heat was gradually taken away from the heat insulating material, and the effect of heat insulating was small.
The field board 6, the stylo home 5, the moisture-proof curtain, and the roof tin, which are used for the roof material, could not be used as a heat insulating layer even though they had a certain heat insulating effect.

In the present invention, the attic is not ventilated, and in winter, the ceiling 13 to the roof totan 3 and the snow cover 13 on the roof are also used as a heat insulating layer to improve the heat insulating property and improve the heating efficiency and the humidity. Is processed so as to be discharged from the pipe 14 on the roof to prevent dew condensation. Also, in the summer, the hot air that collects on the top of the roof is naturally discharged to improve the environment of the living space.

This invention was invented when I built a house (hereinafter referred to as "experimental house") 39 years ago, but as shown in Fig. 1 from that time, the theory of attic ventilation 12 is clear. It was very courageous to seal the attic. The logic I made at this time was that the heat insulation of the roof should be the strictest, as the heat moves up and is eventually released from the roof. Even if the insulation of the roof is neglected and the insulation of windows and walls is increased, the insulation effect does not increase proportionally.
Repairing a bucket with a hole in the bottom is like strengthening the sides of the bucket, and no matter how much you reinforce the sides of the bucket, the bucket is useless unless it prevents water from leaking from the bottom. .. In the same way, he thought that the heat insulating effect of a house would not increase in proportion to the amount of heat insulating material unless the heat that went up to the top and escaped from the ceiling was suppressed.

As for the heat conduction inside the wall, the heat rises even in the object, so the heat dissipates diagonally upward instead of right beside, so the heat insulation effect of the wall is relatively large, but in the case of the ceiling, the heat is generated. Since it rises directly above, that is, at a right angle to the heat insulating material, even if the same heat insulating material as the wall is used, the heat insulating effect is small.
Therefore, we stopped the attic ventilation method, attached heat insulating material, glass wool 10 and styrohome 5 to the back side of the roof as shown in Fig. 2, and built an experimental house that seals the attic and prevents air flow. (Fig. 2). The attic wall was also insulated.
It was a fairly warm house, but in general, the heat insulation effect of each house is difficult to compare with other houses, so I lived thinking that it had a good effect.

Since the roof was sealed as an experimental house, I went up to the roof and inspected it about three times a year to see if there was any damage due to condensation. When I was walking on the roof about 5 or 6 years after the construction, I found a "fluffy feel" in some parts. It was judged that the glue of the control panel used for the field board 6 had peeled off due to dew condensation. I thought, "The theory of attic sealing is broken," but I expected this to happen, so I took the measures I was thinking of.
Since the experimental house has a snow-free roof with a gutter in the middle, that is, an M-shaped roof, holes were made in the high places of the roofs at both ends, and a PVC pipe 14 with a diameter of 75 mm was inserted. I decided to make about 300 holes with a diameter of 3 mm (Fig. 4-19) in the upper part of the attic of the pipe to gradually remove the warm and humid air accumulated in the upper part of the roof. When I put my hand on the outlet of the pipe after installing it, warm air was coming out. When I smelled it, I smelled a faint smell of human life. Thirty years have passed in such a state. The roof seems to have a little more soft spots, but it was fully maintained as a roof because it was painted with galvanized iron and well maintained.

As the number of soft spots on the roof increased, I felt like "I'm about to do something about it" for about five years, so I asked multiple roofing companies to diagnose the condition of the roof. The judgment result was "This is dangerous, I do not know when it will fall", "Since the galvanized iron rusts from the bottom, even if the surface is prepared, it may fall from the bottom." I lived with anxiety, but the strong wind on October 24, 2014, blew off the upper part of the parapet part, and I couldn't stop dubbing the roof.
At the recommendation of the construction company, it was decided to renovate with the attic ventilation specifications that are generally made.

Construction began on March 19, 2016. At this time, the temperature here was minus 2 to 5 degrees in the morning and 4 to 5 degrees in the daytime. It was a great opportunity to see if the roof was rotten due to attic condensation. I was excited to see the dismantling of the construction work. I don't know if the contractor is conscious, but the dismantling started from the most bumpy part of the roof. First, when a part of the galvanized iron was peeled off and turned inside out, there was only rust on the fishing rod, and the other parts still had the same color as when they were new (Photo 1). The result of further peeling is shown in Photo 2. The wood rotted only at the edges of the rafters, and the rafters still had the color of the wood. About 40% of the control panels had the glue peeled off, but the veneer itself that makes up the control panel was not rotten. More than half of the roof had a solid control panel. The insulation was also firmly attached, and the only thing that got worse was the glue on the control panel. It is probable that the glue on the control panel came off due to condensation before the humidity-removing pipe was inserted. If the field board 6 was stretched with a single board, it seems that there was no problem.
From these facts, it was found that the attic sealing experiment conducted over 39 years was "completely successful".

Attic dew condensation is a problem of how the humidity of life reaches the attic, but since it is not clear, in the experimental house, we devised so that the humidity does not penetrate into the indoor walls (Fig. 5). .. As for the walls of the room, a 20 mm styrohome 5 was placed on the indoor side of the pillar, and a 12 mm gypsum board 25 was placed on it. The interior is made entirely of vinyl cloth 26, and the end of the wall and ceiling is designed so that there is no gap so that no daiwa is attached. The number of electric switches and outlets is designed to be as small as possible, and for indoor ventilation, a drain duct from the roof is passed through the center of the experimental house, and this duct is used for 3 rooms on the 1st floor. Natural ventilation was done in 2 rooms on the 2nd floor. There are only two ventilation fans, the kitchen and the bath (same room as the toilet), which are designed to keep moisture out of the walls, but unfortunately we measure how effective these constructions are. It is not possible.
In the future, if you want to build an attic house, you need to pay attention to the movement of humidity from the room.

The construction went smoothly, the roofing material was peeled off, and the glass wool 200 (Fig. 2-10) mm and the styrohome 20 mm (Fig. 2-10) underneath were placed on the ceiling, and the roof disappeared. Soon the living room became cold. I actually experienced that it is difficult for the room to warm up because there is no roof even if there is insulation on the ceiling. There were two nights without a roof, and the cold burned the ondol's furnace at a rate higher than midwinter, but the temperature in the living room did not rise at all.

The construction progressed, the carpentry work on the roof was completed, and all that was left was to roof the tin and leave a glass wool (300 mm) blown.
The temperature in the room was as cold as yesterday because the insulation was not blown that night, and there was no sign of warming up at all. Even when I'm in the house, it feels like the autumn breeze is passing around my skin, and I don't feel warm.
The experimental house uses ondol heating, and the ondol furnace is installed in the basement, so the basement is always warm, but I was surprised that even the basement with the furnace was abnormally cold.
Perhaps the wall of Ondol collapsed inside, and I felt pale for a moment as if the hot air had escaped directly into the chimney, but as a result of thinking, this is now making the roof with "attic ventilation specifications". Because of this, cold air flowed into the attic, and the heat insulation effect was reduced, so it was judged to be cold.

The next day, I immediately contacted the construction company, requested a design change, and completed the work to completely cover the attic ventilation port. Although it was a little colder than the previous experimental house, it returned to the warmth of the previous one.
Through this experience, I confirmed through actual experience that it was very cold when ventilating the attic, but at this time it became cold not only on the second floor but also on the first floor and downstairs, so I was very surprised at that point. .. I think it would get even colder if I kept that condition for days.

Two days later, shortly after the final work of blowing 300 mm of attic glass wool was completed, the room temperature began to rise and it became very warm. This was a testament to the lack of insulation in the experimental homes.
After 30 years of experimentation with the attic sealed, it was found that there was no problem, and that the attic ventilation made the heating worse and it was very cold.
I have never come into contact with experimental data on how the heating effect changes depending on whether or not attic ventilation is performed. Although it was obtained by chance this time, we obtained valuable experimental results that the heating effect changes significantly depending on whether or not attic ventilation is performed.
It is cold when ventilated in the attic and warm when the attic is sealed and insulated. If the snow on the roof is used as a heat insulating layer, it will be even warmer.
This is the whole picture of the remodeling of the roof part in order to utilize the snow cover on the roof, and it is the pillar of the present invention for the time being.
Traditional attic ventilation exhausts even the heat contained in the air. This is more than a measure to prevent dew condensation, it emits heating energy in excess of the required limit, resulting in a huge loss.

It is difficult to numerically display how warm a house is. When it gets warmer, the heat source becomes smaller and the outside air condition is different, so it is difficult to compare with other houses in the same condition. Since the temperature measurement this time was a short period of time and it was also a transition of the season called the snowmelt period, the measurement results are for reference only, but the measured values compared to the heat insulation state of the roof are as shown in Table 1.
The temperature of each room in Table 2 shows the temperature difference between bedtime and wake-up, and does not indicate the maximum and minimum temperatures of the day. During the day, when the sunlight shines into the room, it is about 30 degrees.
During the time period from bedtime to the next morning, since people are sleeping, there is no change in living temperature, there is no influence of sunlight, and the situation where the outside air drops constantly does not change much every day, so the performance of the house It is suitable for measurement, and how many times the room temperature has dropped during this time period is a great guide for knowing the heat insulating effect.

The temperature of the living room in the experimental house had dropped by about 4 to 5 degrees from bedtime to morning, but after adding the heat insulating material this time, it dropped by only 1 to 2 degrees (Table 2.). reference). During the two days of attic ventilation, the room temperature in the living room has dropped by 7 to 8 degrees Celsius. After many days in that state, I think the temperature would have dropped further. The experimental house is equipped with a heat-insulated door (a door with a styro home 20 mm inside) that looks like a shutter in the direction of Honshu inside the window. It closes when the sunlight does not enter to prevent the temperature inside the room from dropping. In addition, the windows are all window pair glass with a middle window attached, and the living room and the small rise are equipped with a vacuum glass three-layer window (Spacer 21).

Note the hall leading to the entrance, which is the coldest place on the north side of the experimental house. This hall is separated from the entrance by a glass door, but it has a 6 tatami mat room including the stairs, and the 2nd floor has 12 tatami mats including the hall and the playroom, which is connected to the 1st floor hall. .. The bottom of the entrance hall was cold and I couldn't help. I didn't know the cause and thought that the heat insulation of the entrance was bad, but when I reinforced the heat insulation of the roof part with this construction, this hall became warm. In short, since the heat radiation from the ceiling on the second floor is small, the lower part of the hall is also warmed up, and as a result, the bottom of the hall is warmed up. In this way, the quality of the heat insulation of the ceiling not only changes the temperature of the room on the second floor, but also changes the temperature of the whole house straight.

According to the present invention, the attic is sealed to prevent cold air from entering the attic, and the attic is firmly insulated (FIG. 3) to raise the temperature of the attic and enhance the heat insulating effect. When the heat insulating material is added in this way, the temperature of the attic becomes high and the heat radiation from the room becomes significantly small. Therefore, the heating effect is improved, and the fuel consumption is reduced. That leads to a reduction in carbon dioxide for the time being.
Comparing the heat insulating layer of the conventional attic ventilation specification (FIG. I) and the heat insulating layer of the present invention (FIG. 3), the difference, that is, the difference in thickness and density of the heat insulating material can be determined at a glance. In the present invention, not only the thickness of the heat insulating layer but also the method of inserting the heat insulating material is meticulous, and the heat insulating effect is very high. There is no particular rule on how to insert the heat insulating material, and in short, it should be designed to improve the heat insulating material.

With such a structure, the snow on the roof will be connected to the roof to form a heat insulating layer. It is generally thought that snow is cold and cold, but when snow accumulates as much as 30 cm, it does not freeze underneath.
I lived in the cold region of Tokachi, Hokkaido, where my father was farming until he was 19 years old. In a normal year, the area becomes frozen soil about 50 cm deep. However, in the year when heavy snow fell before the soil in the beginning of autumn froze deeply and it became a heavy snowfall, when the snow was dug after the beginning of the year, the soil was not frozen. From this experience, it was found that when snow accumulates to some extent, the soil beneath it does not freeze.
From this, it can be seen that when the amount of snow on the roof reaches 50 cm, the temperature of the lower surface of the snow becomes about zero. Since it does not freeze even at the temperature of the earth in winter, it is presumed that the roof of the house stores more heat, so it is judged that the bottom of the roof snow does not fall below zero. This means that the temperature of the attic will not drop any further, so there will be less condensation.

Ishikari City, Hokkaido, where the experimental housing is located, has a low temperature of about -15 degrees Celsius in the midwinter. In addition, the northwest wind blowing from Ishikari Bay is strong and often exceeds 10 m / sec. Therefore, the sensible temperature of the outside air is -25 degrees or less.
If there is no snow on the roof, the tin on the roof will be exposed to a low temperature of -25 degrees, so the insulation covers a range of 50 degrees from the living temperature of around 25 degrees to the outside temperature of around -25 degrees. You have to.
However, if there is snow on the roof, the roof surface is near zero degrees, so the heat insulating layer should cover a width of about 25 degrees. In this way, whether the heat insulating material covers the width of 50 degrees or the width of 25 degrees is a decisive difference. It can be seen that the heat insulation of northern houses differs significantly depending on the shape of the roof, whether or not there is snow on the roof, that is, whether it is a roof that drops snow or a roof that puts snow on top.

Therefore, the heat insulating layer of the present invention may cover from about 23 degrees to about zero degrees of human living room temperature when there is snow in winter.
This means that even in the extremely cold regions of Hokkaido, if you use the heat insulation of snow, you can think of it as equivalent to roof insulation in the Kanto region.
The heat insulating layer of the conventional method covers a range of 40 degrees or 50 degrees with a glass wool blowing of about 300 mm (Fig. I-10), whereas in the present invention, a huge heat insulating material covers about 23 degrees. You just have to. Compared with the conventional method, there is a difference in the temperature covered and the amount of heat insulating material. In addition, in the conventional method, since the cold air layer is on the glass wool, the heat becomes an updraft in the glass wool and is quickly discharged. The present invention is devised so that the heating temperature is used for a long time by keeping the heat as little as possible and staying in the heat insulating material or the attic for a long time. If heat insulation is applied by the method according to the present invention, it is possible to insulate the roof portion, which is incomparable with the conventional method, even if there is no snow on the roof.

Prevention of dew condensation on the attic is carried out by attaching a pipe (Fig. 3-14) that escapes from the attic to the top of the roof and gradually discharging highly humid air from this pipe (Fig. 4). The amount of air discharged from the pipe needs to be appropriately adjusted (21 in FIG. 4) depending on the shape and area of the roof.
If too much is put out, the heating effect will be small, but it will not be cold like a conventional house because there is no opening for cold air to enter like attic ventilation. In addition, if the amount of discharged air is too small, it may cause dew condensation. It is necessary to adjust the amount of exhaust air from the pipes in consideration of the climate of the area where the house is located, the measures against humidity in the residential area of the house, the number of people living in the house, and the lifestyle. Further, the displacement can be adjusted by the hole (21 in FIG. 4) made in the cap at the tip of the pipe. Although the adjustment mechanism is a little complicated, any switchgear such as a shutter valve can be used regardless of whether it is automatic or manual.

The pipe can be installed at the top of the roof and stretched vertically, or it can be bent immediately on the roof so that it sticks out of the roof and is discharged to the side where the cornice cannot be covered. You can also take it and eject it upwards.
Since the temperature of the attic is high and the air containing a lot of humidity is discharged, it is better to give the roof a gradient of about 2 inches as a place to retain warm air. The slope of the roof is also convenient for bringing snow on the roof.
In order to ensure this construction method, it is necessary to accumulate the experience of many architects in the future.

Since dew condensation may occur inside and outside the moisture discharge pipe (Fig. 3-14) during the winter season, attach a cap (17 in Fig. 4) to the lower end of the pipe so that the dew condensation melts and collects at the bottom of the pipe. Also, in case of dew condensation on the outside of the roof pipe, it is advisable to place a container-shaped water reservoir on the bottom of the pipe so as to collect water droplets. The accumulated water evaporates naturally.
To prevent dew condensation, an electrically operated dehumidifier may be used to circulate the attic air to dehumidify. This method is highly effective in preventing dew condensation. It requires electricity and needs to be inspected properly.

By adopting the attic sealing method, it can be used as a heat insulating layer in which the ceiling material and the tin of the roof are integrated, and if there is snow on the roof, the snow is also used as a heat insulating material. (13 in FIG. 3). Therefore, the heat insulating layer of the present invention becomes heavy (Fig. 3-16) and exhibits a large heat insulating effect.
In the present invention, the air in the attic is kept as small as possible to reduce the heat loss due to convection, the heat is stored in the heat insulating material or the attic air, and the heat is utilized for as long as possible.

As a result of my 40 years (38.5 years to be exact) of experiments on attic dew condensation, it was proved that it can be completely prevented by removing moisture with a pipe such as vinyl chloride.
If you build it in the structure shown in Fig. 3. The heat insulation of the roof is strengthened, the heat of the first floor rises to the second floor, and the heat dissipation from the ceiling is extremely small, so in the experimental house, the room temperature on the second floor is 20 degrees or more, and most of the second floor needs heating. Is gone. (Depending on the design of each house, in the experimental house, there is no insulation on the second floor)
So far, the explanation has mainly focused on M-shaped roofs, but this can also be applied to roofs such as gables and roofs with a ridge shape.
In midsummer, the hot air stays at the highest point of the roof, so if you drain it, the hot air in the house will be somewhat less. Also, when the outside temperature drops in the evening, the temperature of the attic also drops, which makes it easier to surpass the room.
If hot air is stored in a high place on the roof, the effect of hot air discharge is good, and if a pipe is used, there is also a draft effect of the pipe, and heat can be discharged more efficiently.
In the conventional construction method, this attic hot air is discharged by attic ventilation, and the ventilation opening is provided in the attic, but most houses are located at the bottom, so the hot air is downward. It was difficult to dissipate, and it was difficult to discharge hot air.

1 By increasing the heat insulation of the roof, the heating efficiency is significantly increased.
2 Fuel consumption will be reduced (it is judged that 20 to 30% or more will be reduced).
3 The snow on the roof can be used as a natural heat insulating material.
4 Carbon dioxide emissions are reduced.
5 Since the humidity is removed from the attic with a pipe, there is no dew condensation on the attic.
6 The whole house gets very warm. If you heat on the first floor, there is almost no need for heating on the second floor.
7 Even if the heating is turned off, the warm heating effect continues for a while.
8 Construction is easy and any carpenter can make it.
9 The cost is very low compared to the effect. 10 You can easily remodel an existing house into an attic closed type.
11 It can be applied not only in cold regions but also in any region.
12 In the summer, the attic heat is exhausted, so the cooler works and you can live cool.
13 The sound of rain hitting the tin roof becomes very small.
14 The soundproofing effect from the outside is increased. Reduction of airplane noise.
15 Insects such as bees and small birds do not enter the attic.

Insulation cut diagram of a house with conventional attic ventilation. Insulation cut-out of experimental house I tested for 39 years Insulated cuts of the house according to the invention, without attic ventilation, strengthen the insulation of the roof and use joists to withstand the weight of snow. A pipe that discharges air with high humidity and temperature. A cut view of the wall composition of the experimental house.

The present invention will be described with reference to FIG. The attic surrounded by the roof 1, the wall 2, and the ceiling 3 is not provided with a ventilation port by the conventional method, and is designed to be sealed as much as possible.
For the wall, put 100 mm of glass wool between the pillars, and put glass wool with a thickness of 50 mm or more on the indoor side. For the roof, a styro home of 30 mm is stretched from under the purlin, and joists are struck on the purlin. Put 200 mm of glass wool between the purlin and the joists, and put a field board on it. Avoid plywood as the field board, and use veneer. Spread 20 to 30 mm of Stylo Home on top of this, cover it with a tarpaulin, and cover the tin roof. In the construction, it is necessary to construct the styro home so that there are no gaps.
On the ceiling, glass wool is blown to fill the ceiling. In this case, the high part of the roof should have a space as a moist air pool.
Further, the heat insulation of the attic can be made more completely by spraying urethane foam or the like on the attic wall and the attic from the ceiling side by about 50 to 100 mm.
Rafters are used for conventional roofs, but in the present invention, a certain amount of snow is expected on the roof, so in order to increase the strength of the roof, it is better to use joist instead of rafters. desirable.

In order to prevent dew condensation on the roof, a hole is made in the high part of the roof and a vinyl chloride pipe of about 75 mm is inserted to discharge the required amount of air containing a large amount of humidity and high temperature in the attic.

It can be used anywhere as a heat insulating method for the roof of a general house.

1 Roof 2 Walls 3 Totan Board 4 Waterproof Sheet 5 Stylo Home 6 Control Panel 7 Single Board (Field Board) 8 Rafters 9 Joists 10 Glass Wool 11 Ventilation Port 12 Ventilation 13 Snow Cover 14 Ventilation Tube 15 Ceiling 16 Insulation Layer 17 Cap 18 Insect Net 19 Exhaust Suction hole 20 Cheese 21 Exhaust outlet 22 Painting 23 Foam concrete board 24 pillars (100 x 100 mm) 25 Gypsum board 26 Interior (vinyl cloth)
27 Exhaust pipe body

Claims (1)

It is a building method that integrates the snow on the roof with the roof of the house and uses it for heat insulation.
A construction method that uses pipes to exhaust air from the upper part of the attic to prevent dew condensation on the attic in winter and reduce indoor heat in the summer to release moisture and hot air (summer) from the closed attic. In
The roof is an M-shaped roof with a gutter in the center, and exhaust pipes that extend vertically and penetrate the roof are installed at the top of the roofs at both ends, and the attic is provided with ventilation means other than the exhaust pipes. Sealed without
An exhaust volume adjustment mechanism is provided at the outdoor end of the exhaust pipe, a large number of small-diameter exhaust suction holes are provided at the location corresponding to the upper part of the roof of the exhaust pipe, and the end of the exhaust pipe on the roof is capped. Close the lid with
A building method that exhausts warm and humid air that stays in the upper part of the attic through an exhaust pipe.

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