Polyurethane foam - how to use and not doubt the end result

Professional mounting foam TECHNONICOL 240 fire-resistant 1000 ml. Photo Petrovich

Polyurethane foam has many advantages , one of which is ease of use . But despite this there are some nuances . And for beginners who do not have construction skills, difficulties may arise. To eliminate the possibility of problems, the following information is presented.

Scope of application of construction foam

Polyurethane foam, which can be purchased at any hardware store, is intended for installing window and door structures. It can also be used when installing various pipes and electrical equipment.

The composition has excellent thermal insulation characteristics. If there are cracks and gaps in the walls, cracks in heating systems, construction foam will help eliminate the defect. The hermetic composition also allows you to attach various wall panels to the rough surface.

All this provides not only decorative properties, but also moisture insulation. Using polyurethane foam, you can reduce the heat transfer of metal baths made of cast iron or steel. It is enough to treat the surface with a sealant from a can.

GOST 30971-2012 for installation of plastic windows

GOST 30971-2012 for a window system specifies general technical conditions for installation seams and joints of window systems to wall openings. The norm is valid in the Russian Federation and 5 other CIS countries. “Installation of a plastic window according to GOST” requires clear measurements of the slope of the profile relative to the opening. Checking is carried out with a plumb line and level.

At the installation step, it is fundamentally correct to calculate the number and placement of anchors in accordance with GOST. To install a double-hung window, 14 anchors are needed. This amount seems unnecessary, but compliance with the requirements of GOST 30971-2012 guarantees the durability of the PVC window. Laying a 3rd layer of seam for vapor barrier is also irrational, but it increases the service life of the heat insulator by 2-3 times.

Types and forms of release

You can find construction foam of various types and release forms on sale. The choice depends on the conditions under which it will be used. The difference is this:

• Household foam - produced in small cans, the volume of which is 600-800 ml. The kit comes with a special tube that makes working with the sealant easier. Despite its domestic purpose, the characteristics of the composition are almost similar to professional foam. In addition to the straw, you can purchase a gun separately if finishing work requires it. This type is intended for eliminating gaps, cracks, minor repairs, and gluing some surfaces.
• Professional construction foam - as a rule, is supplied in large cylinders with a volume of 1.5 liters or more. To use sealant, you will need a special gun, since a lot of pressure is created to release the foam. Construction sealant is intended for performing a large volume of work.

When choosing polyurethane foam, you should also pay attention to the instructions on the can. The manufacturer indicates at what temperature conditions the selected type of foam can be used. Also, construction sealant can be used for winter and summer purposes.

For all-season work, universal polyurethane foam is provided. Be sure to pay attention to the flammability class. Materials marked B1 are considered fire-resistant, self-extinguishing – B2 and flammable – B3.

You also need to pay attention to the composition, which can be either two-component or one-component.

On the bottles the manufacturer indicates what the use may be:

• Disposable – the foam is intended for one time use only. And even if there are leftovers in the cylinder, it will not be possible to use it in the future. Therefore, you can immediately throw away the cylinder.
• Reusable – polyurethane foam can be used several times. Even after time, the residues in the cylinder will not deteriorate.

Should there be a pistol or not?

If you can work with household foam with a tube, then why buy a professional cylinder that requires a gun? An unreasonable waste of money, and that's all. That's how it is. However, experts (including myself) still recommend using “weapons”. Why? Well, maybe because it is known for the following benefits:

• minimum consumption - the gun releases foam in doses, and the tube leads to excess consumption of the substance by 2-3 times;
• accuracy - the gun nozzle is very narrow, and is also adjustable, which allows you to fill even the tiniest cracks;
• speed - 10-30 seconds are enough to make a 2-meter seam, and you will have to work with the tube for about 15 minutes (of course, all this is figurative and depends on the specific working conditions).

An anecdote on the topic: - How did your husband let you go to a nightclub? - Yes, I prepared a bath for him and filled it with foam! - And that stopped him? — Polyurethane foam will stop anyone.

Polyurethane foam sealant is a universal tool that allows you to easily deal with any cracks, gaps, cracks and voids, even in the absence of a gun. Although not as high quality, but still...

Wishing you fast and high-quality work, dear fellow builders! See you!

Wisdom Quote: Knowledge is always preceded by a sentence (Alexander Humboldt).

How to use it correctly

At first glance, it seems to many that there is nothing complicated about sealing seams, but in the process some difficulties and additional material costs may arise. Therefore, before starting work, you should learn how to use polyurethane foam correctly.

• Inexperienced users make a big mistake when applying foam to a dry surface. For the sealant to begin to harden, a humidity level of approximately 50 percent is required. Therefore, before carrying out construction work, you need to properly moisten the surface using a spray bottle.
• It is also unacceptable to apply a second layer of foam if the previous one has not been moistened. If you need to apply a second layer of foam urgently, just moisten it and wait 10 minutes, and then apply. In this case, the sealant will not peel off and will lie tightly on the surface.
• Before using the composition, you must use protective gloves. If the foam gets on your skin, it will cause a burn.

Polyurethane foam sealant: a little theory

How to work with sealant without a foam gun? Very simple. But first, let's talk a little about the main character of this article - foam. For what? And then, to understand the principle of operation of polyurethane foam. I think no one wants to ruin the substance and the home. It is so? Great. Then let's get started.

Story

The sealant was born thanks to the German chemist-technologist Otto Bayer. He invented the substance back in 1937. Or rather, he discovered polyurethane. And in 1970, specialists from an English company invented polyurethane foam sealant.

It has been tested and improved over the years. In 1980 it was used by construction workers in Sweden. The invention was to the liking of many maestros of architectural art, since it had a number of positive properties.

Today, of course, sealant is produced in many countries. For its production, exclusively innovative technologies are used.

Concept

Polyurethane foam or polyurethane foam sealant is a substance that consists of two components - polyols and methyl...ate (you'll break your tongue there). In addition, in the manufacturing process of the product, stabilizers, catalysts, a mixture of butane and propane, etc. are used.

Popular questions is it possible

Application of polyurethane foam is possible for various purposes. Many users ask various questions about the use of this sealant. To dispel all doubts, we will answer the main exciting questions.

Foam the wiring

During renovations, many people have a question: is it possible to foam the wiring in the wall? As for sealing cable penetrations, in such cases you cannot even use fire-resistant polyurethane foam. If a fire occurs, the foam will melt in any case, and smoke will flow into adjacent rooms. Also, you cannot foam grooves with wires. For this it is better to use gypsum compounds.

Wires can be foamed with foam in a concrete wall if there are no twists. But if you need to replace the wiring in the future, there will be access issues because the foam is difficult to clean.

Foam the socket

Polyurethane foam is used for various purposes, including using it to foam the socket if necessary. The socket boxes are securely and securely attached to construction sealant.

The most important thing in installation is to prevent the polyurethane composition from getting on the contacts. Before starting work, you need to unplug the outlet from the electricity. After complete drying, it is recommended to cover the foam with plaster.

Foam heating pipes

This question worries many during the construction and renovation of premises. The answer here is the following: it is not recommended to foam pipelines that pass through walls or partitions. In general, the use of any flammable insulation materials is prohibited.

However, there are no clear prohibitions on the use of polyurethane foam if it has fire-resistant properties. Therefore, if you need to foam heating pipes, this must be done using a composition that is resistant to high temperatures.

Foam the bathhouse from exhaustion

The widespread use of construction foam often leads to the question: is it possible to foam the cracks in a bathhouse from the inside? In general, this is not recommended, but it is not prohibited either. It is simply not practical to use a synthetic compound with environmentally friendly materials.

In bathhouses, as a rule, the decoration includes boards, timber, and natural stones. Also, under the influence of high temperatures, polyurethane will begin to melt, releasing harmful substances. Therefore, foam cannot be used in the steam room. It is better to give preference to sealants that are not afraid of high temperatures.

If the use of foam is unavoidable, it is necessary to choose professional compositions with fire-resistant properties.

Foam the log house

Using construction polyurethane foam, you can only temporarily foam a log house. This material is not suitable as a permanent sealant in joints for the following reasons:

• The environmental friendliness of a wooden structure is compromised.
• Construction foam does not have elasticity, which in turn can lead to cracks in a wooden frame.
• Wood is a breathable material, and foam will clog it. Moisture and rot will appear at the junction of wood and polyurethane.

Should there be a pistol or not?

If you can work with household foam with a tube, then why buy a professional cylinder that requires a gun? An unreasonable waste of money, and that's all. That's how it is. However, experts (including myself) still recommend using “weapons”. Why? Well, maybe because it is known for the following benefits:

• minimum consumption - the gun releases foam in doses, and the tube leads to excess consumption of the substance by 2-3 times;
• accuracy - the gun nozzle is very narrow, and is also adjustable, which allows you to fill even the tiniest cracks;
• speed - 10-30 seconds are enough to make a 2-meter seam, and you will have to work with the tube for about 15 minutes (of course, all this is figurative and depends on the specific working conditions).

An anecdote on the topic: - How did your husband let you go to a nightclub? - Yes, I prepared a bath for him and filled it with foam! - And that stopped him? — Polyurethane foam will stop anyone.

Polyurethane foam sealant is a universal tool that allows you to easily deal with any cracks, gaps, cracks and voids, even in the absence of a gun. Although not as high quality, but still...

Wishing you fast and high-quality work, dear fellow builders! See you!

Wisdom Quote: Knowledge is always preceded by a sentence (Alexander Humboldt).

How long does it take to dry?

Construction foam has many advantages and excellent properties. Among all the advantages, ease of use, low thermal conductivity, low shrinkage and much more should be highlighted. Before using foam, you should study all the parameters, the main one of which is drying time. Having found out how long the polyurethane foam takes to dry, you can accurately answer the question of when to start further work with the seams.

First of all, the polymerization time depends on the ambient temperature and layer thickness. If you use foam under normal conditions, then all excess can be cut off after 3 hours. Final hardening occurs in 9 to 12 hours.

Many people are often interested in how long it will take the foam to dry when installing windows or doors. The composition can dry for too long only due to improper use. The foam may have been used in an environment with the wrong temperature. If you need to install windows in the cold season, you need to purchase special winter polyurethane foam.

Preparatory stage

Having completed the preliminary analysis and drawing up a work plan, you can begin the preparatory stage. It consists in preparing surfaces and eliminating those factors that theoretically interfere with the foaming process.

Algorithm of actions:

1. Carefully and effortlessly clean the tip of the gun with which the product is applied. In most cases, the cylinder is tightly screwed to the gun.
2. In winter, the installation material needs to be heated. To do this, just place the balloon in warm water, or leave it next to a heat source. It is important not to overdo it with the heating temperature, otherwise the container will explode.
3. If installation occurs in the summer, the temperature of the cylinder decreases. Otherwise, during the work it will involuntarily expand, which will create voids in the opening.
4. Shake the container well. It is important to shake the container already screwed to the gun. If you shake it separately, the internal pressure of the cylinder will rise and it will be difficult to screw it into the gun.
5. Carefully examine the surface of the opening and remove dust from it. A vacuum cleaner will do. If installation occurs in winter, then attention is paid to the formed ice. If there is one, it is removed.
6. Apply a little warm water or primer (if the wall is made of aerated concrete) to the surface of the opening. It is best to use a sprayer.

Advice! Experienced builders recommend moistening the foam with water after application, then it will dry a little faster.

Also, close attention is paid to the mounting gun. If it has not been used for a long time (more than 24 hours), or a zero cylinder has been attached to it, then you will need to empty a little into an unnecessary bag or trash can. However, you must press firmly and not hold.

Important! If the liquid is brought to the correct consistency, then its exit from the gun will be accompanied by certain sounds. If there is no sound, it means the consistency is poor quality.

Otherwise, there is a possibility that the liquid will come out too concentrated and thin. Such a container will not cling or stick to the surface. It will simply slide along the wall. By waiting until it hardens, it is easier to detect gaps inside, due to which technological indicators will not be met.

Consumption for insulation and other work

You can purchase polyurethane foam in cans of different sizes. The first thing to consider is the type of work. If you choose a 300 ml bottle, you will get about 30 liters of composition. This is enough to install one interior door.

Approximately 500 ml is enough to install two plastic windows. But all this is only under ideal working conditions. Therefore, in reality, one cylinder may not be enough. Consumption also depends on the content supplied. A gun will allow you to use foam more economically.

Preparing the work area

Since it is possible to correctly replace an interior door only if a certain sequence of work is followed, all stages should be considered in more detail. You need to start, of course, with preparing the surface. If you had a door installed in the opening, it must be removed.

First, remove the canvas. Then you need to remove the trim from the door. How to do this will depend on the way they are attached. If the structure was installed using glue or using the tongue-and-groove method, it is enough to lightly pry the elements and pull them to the side. It's a little more difficult if the trim is nailed to the box, in which case you can use an ax to pry it up and tear it off the base. After this, you need to carefully remove the door frame. It is recommended to remove all fittings, namely the lock and hinges; they will also need to be replaced.

First of all, you need to dismantle the old door

To simplify the process, use a grinder and a crowbar. Saw the box in half and tear its parts from the wall in the opening. This is not difficult to do, but you need to minimize the destruction of the walls in the room.

If serious damage cannot be avoided, preliminary alignment of the sides will be required.

Saving Tips

Using polyurethane foam, many users want to save on the costs of this material. In general, this is possible if you take into account some tips.

• Working with polyurethane foam without a gun can be very expensive. Therefore, it is still recommended to use a nozzle with adjustable foam flow. All this will allow you to get rid of unnecessary expenses during repairs.
• Before purchasing, you need to carefully consider what volume of cylinder you need to buy. If you purchase a large bottle and use only half, the remaining composition will become unusable over time.
• After use, the gun must be washed to remove foam with a special substance. You can purchase it at construction stores where the foam was purchased.
• Do not press the trigger too hard so that the foam comes out smoothly and in small quantities.

Polyurethane foam is a universal product that can be used in construction and repair. When buying a can, be sure to look at the expiration date. Expired foam will not perform its main functions, and money will be wasted.

You should also remember that polyurethane is exposed to ultraviolet light. Avoid direct sunlight on the foam. If you used the composition to foam the walls outside, additional finishing will be required.

How to cover foam on plastic windows from the street

To close the hardened protection from the street, it is recommended to use a waterproofing agent. A multifunctional sealant or waterproofing tape with a vapor permeability effect is suitable. Using this material will allow you to neatly close the seams on the front side without overlapping.

After installing the ebb, a vapor-permeable material is installed under it. It is important to measure correctly, then cut along the length of the window frame, taking into account the margin for installation under the external slope. If the existing width is not enough, then an additional piece of tape is cut off.

Additional recommendations from professionals

When working with small cracks up to 1 cm, it is more effective to use special sealants or putties. Due to their high ductility, they fit correctly onto the crack without additional expansion.

To work with cracks and holes larger than 10 cm, it is necessary to use static materials. For example, brick, timber, insulation (foam plastic, mineral wool) and additionally treated with polyurethane foam (MP).

When isolating medium-sized cracks, MP is the best option. It has the highest adhesive properties with almost any building materials. But it is advisable to use it for processing polyethylene, Teflon, and silicone.