A cold roofs construction is a simple general protect that a building from atmospheric precipitation. This relatively budget option is often used as an intermediate solution for the further arrangement of a roofing cake with insulation, hydro, and vapor barrier. Cold roofing is mainly done on farm buildings, houses with non-residential attics, gazebos, summer verandas/kitchens. To obtain the desired result, you need to know what it consists of, what materials are most effective and what manufacturing technology should be followed.
Cold Roof Benefits
Uninsulated roofing, which consists only of roofing material and a waterproofing layer, has many positive characteristics. Especially worth noting:
- the possibility of arranging the roof with your own hands;
- lack of financial severe costs (in contrast to a warm roof, the cost of materials is reduced by almost 2 times);
- speed of installation work;
- simple installation technology.
If the attic is not used as a living space, why do we need to insulate it – any sane person makes such a conclusion. A cold roofs construction of a house, despite its obvious drawback, has several advantages:
- savings on roofing materials;
- savings on heating the home;
- ease of installation – installation of a cold roof is much easier.
Cold Roof Installation
The cold roof pie looks pretty primitive:
- Waterproofing layer;
- Sheathing system;
- Roofing material.
It is known that thermal insulation and finishing materials account for about 60% of the cost of a roof. Therefore, the financial benefits of a cold roof are enormous.
Is Cold Roof Waterproofing Necessary?
Waterproofing is necessary to protect the roof structure from condensation that forms on its surface during temperature changes. Although the roof will not be heated, the temperature under the roof and outside will be different. Therefore, there is a high probability of condensation formation, which adversely affects the metal. So, a waterproofing layer is a must for any roof.
Insulation of the Cold Roof of the House
A cold attic (or attic), in principle, can be called a spare living space since, if necessary, the roof can be insulated, thereby expanding the living space of the house. Therefore, if you want to protect the roof, there will be no unnecessary problems: the cold roofs construction cake is the base layer of a full-fledged cake, i.e., it is enough to lay the insulation on the finishing of the roof.
What is equally important – when insulating a cold roof, a vapour barrier layer is not needed since the steam generated inside the room will pass through the insulation, getting into the under-roof space. So, it is recommended to carry out the processing of wooden structures with a unique composition that protects against decay.
You can also use polyurethane foam to insulate a cold roof. Moreover, it is recommended to use it. Such insulation is the best for several reasons:
- with its help, polyurethane foam creates a continuous layer of insulation, i.e., there will be no cracks in the roof of the roof, and the rafters will also be closed;
- it is not subject to decay, as well as to acids and alkalis;
- it is not flammable.
In addition, polyurethane foam has excellent thermal insulation properties. But unfortunately, such a fantastic material also has its drawbacks – it is high cost and the need for special equipment (by the way, also not cheap) for installation. Therefore, you will not be able to install such insulation yourself – you will have to contact a specialist.
How to Make a Cold Roof From Metal Tiles – Installation Instructions
When building a private house, specialists use all kinds of roof designs, but they often install a cold roof. This is ideal when the attic is not intended to be used as a living space. Below we will talk about how to properly install a cold metal roof.
The Advantages of This Option
The device of such a roof is quite simple – you will need to build a structure, lay a layer of waterproofing, lathing, and counter battens roofing. When erecting a cold roof, the main thing is to provide a ventilation opening for the possibility of removing condensed moisture. This is necessary so that the supporting structure and the roofing material do not deteriorate under the influence of water.
What is a Cold Roof?
Cold metal roofing services NYC technology involves the initial construction of a rafter system. A membrane and a plastic film will be laid on it to ensure waterproofing. The counter-lattice, the lathing is stuffed, and the roofing is applied in a metal tile.
Such a roof is characterized by the fact that there is no need to install thermal insulation for it – all that is required is to equip ventilation outlets under the ridge and on the slopes to remove moisture. Make sure that all preliminary calculations are made as accurately as possible.
Roof Installation Has the Following Features:
- If you plan to equip a warm roof over time, then the choice of a membrane to protect against moisture should be careful. If you plan to provide the attic, then a PVC membrane must be present.
- Suppose the roof is not planned to be insulated in the future. In that case, it will be necessary to install micro-perforated waterproofing, which is explicitly used for cold roofs construction. Thermal insulation cannot be installed with such a film; however, you will need to purchase a new membrane in case of further insulation. Otherwise, the roof will lose its protection from moisture in the future, the insulation will not have time to dry, and the roofing material will begin to rust over time.
Cold Roof Installation Steps
When laying the membrane to protect it from moisture, it should be borne in mind that it should remain with a slight sag, about 20 mm. Thus, it will be possible to achieve drainage of condensed moisture, thereby protecting the rafter system and other elements of the roof from decay. To allow water to evaporate on time without stagnating and thereby creating an unfavorable environment, care should be taken to include in the project a ventilation gap, which is located between the moisture-repellent film and the ridge of the roof.
Roofing Cake Structure for Metal Tiles Including Waterproofing
Covering a cold attic with metal tiles is the most convenient and simple way to equip a roof. In this case, the roofing cake will consist of a waterproofing material laid on a rafter frame, lathing and roofing (metal tiles). Actually, the laying of such a coating is done very quickly. The insulating film is fixed with staples or nails. It is additionally pressed with a counter-lattice screwed on with self-tapping screws. The lathing slats are laid, taking into account the size of the metal tile. The board for the lathing is taken with dimensions of 25-100 mm, and sometimes plywood or particle boards are used if continuous flooring is required.
So, a Cold Roof Will Include the Following Layers:
- A vapor barrier is laid for the cold roofs construction from the inside of the room, which only releases moisture to the outside and does not allow it to penetrate into the living rooms.
- Next, a roof truss frame is installed.
- The next layer is waterproofing material. The film is laid with sag to drain condensate.
- Next, a counter-lattice is attached, which presses the waterproofing, securing it, and provides ventilation gaps.
- Then the crate is stuffed to fix the roofing. It is made of 50 × 50 mm slats and is laid along the slopes with an indent of 35-45 cm. Based on the type of roofing and the slope of the slopes, the pitch of the sheathing and the thickness of the board for it may differ.
- The last is the flooring of the metal tile.
The Specifics of the Installation of Cold Metal Roofing
Today, in constructing a residential building, various roof structures are used, but the simplest is a hard roof. Such a device is great when the attic space is not used as an additional living space. The same roof scheme is straightforward: supporting structures, waterproofing, lathing, and counter-lathing plus roofing material.
Cold-Type Roofing Scheme
A cold roof differs from a warm one in its structure, although its design itself is straightforward. The only thing to consider is the roofing option. When using metal tiles, a ventilation gap should be provided to correct condensate drainage from the under-roof space. This is done to prevent the steel sheet from corroding.
A cold roofs general construction in NYC device is the installation of a rafter system. A membrane or polyethene film is laid for waterproofing. After that, a counter-lattice, a lathing, and a covering in the form of a metal tile are nailed.
The peculiarities of such a roof are the complete absence of a heat insulator layer, the presence of ventilation outlets under the ridge and on the slopes to remove moisture. Design and installation are not complex, the main thing is to correctly carry out all the preliminary calculations.
The Installation Itself Includes the Following Features:
- Suppose in the future it is planned to install a warm roof. In that case, you need to approach the choice of a membrane very carefully to protect against excess moisture. For the future attic, only specialized waterproofing in the form of membranes made of PVC is suitable.
- If further insulation is not planned, then micro-perforated waterproofing is used, designed specifically for cold roofs construction. Such a film does not allow thermal insulation materials to be laid next to it; that is, with further insulation, you will have to spend money on a new membrane. If this condition is not met, then the roof will practically not be protected from moisture in the future. The insulation will be constantly wet, and the roof covering will corrode.
What Else is Required?
To mount a roof with such a structure, it is necessary to take the most straightforward tools and materials that do not differ in high cost. In addition to wooden boards for constructing the rafter system, lathing and counter-battens, a vapor barrier, a waterproofing membrane, and the estimated number of metal tiles sheets should be prepared. Brackets, galvanized nails, self-tapping screws for wood and metal are used as fasteners. When calculating steel sheets, it must be remembered that various additional elements may be needed, for example, ridge tiles, valleys, cornices, etc.