Building an extension to the house with your own hands

Constructing an addition to your home can be a fun and fulfilling undertaking. Whether you want to increase the value of your property, create a new home office, or simply need more living space, doing it yourself can save you a lot of money. Careful planning and the appropriate approach will enable you to build a seamless addition that fulfills your requirements and enhances your current house.

It’s critical to comprehend the project’s scope before you begin. The design of your extension, the materials you’ll use, and local building codes are just a few of the things you’ll need to think about. You can stay on course and steer clear of common pitfalls with the aid of a clear plan.

Consider the foundation next. Any extension needs a strong foundation because it keeps the structure stable and supports it. The size of your extension and the type of soil you have will determine whether you need to use concrete slabs or dig deep trenches. At this point, careful planning will lay the foundation for a successful build.

The walls, roof, and interior can be built after the foundation is complete. Although each step will need close attention to detail, if you are patient and committed, you will see your extension come to life. Never forget to take your time and ask for help if you’re unsure of any step in the procedure.

Step	Description
Planning	Decide on the extension"s size and purpose. Check local building codes and get any necessary permits.
Design	Create detailed plans or blueprints. Consider hiring a designer if needed.
Foundation	Excavate the area and lay a solid foundation. This might involve pouring concrete or setting footings.
Framing	Build the framework for the extension using timber or steel. Ensure it"s sturdy and level.
Walls and Roof	Construct the walls and roof. Install insulation and weatherproofing as needed.
Windows and Doors	Install windows and doors. Make sure they fit properly and are sealed to prevent leaks.
Interior	Complete the interior work, including drywall, flooring, and painting. Install electrical wiring and plumbing if needed.
Finishing Touches	Add final details like trim, fixtures, and landscaping around the new extension.

Requirements for premises

You can use your hands to build an addition to the house. The best results occur when the design of the room blends in with the overall style of the house. However, this isn’t always the most crucial element; what matters most is that the extension is strong and well-made. Many decide on a frame addition to the house because of its dependability and light weight. It is swiftly constructed, dependable, and economical.

Consider every detail beforehand. Every kind of room has subtle differences. Unlike an additional room, the veranda lacks heating. If this is going to be a kitchen or bathroom, run pipes and utility lines before work starts, and take care of any insulation and waterproofing afterwards.

Foundation device for an extension

The foundation’s arrangement is the most crucial step in the building of an extension. If the owner was involved in the building of the house, he is fully aware of the subtle differences in the layout and dimensions of the original foundation. There may not be such information available when purchasing a ready-made home. In this situation, you must excavate a hole close to the house’s wall on your own, measure the foundation’s depth, and ascertain the type of soil.

It is recommended that you stop at a foundation that resembles the house’s base. Certain foundation types interact with the soil less well than others, which can put undue strain on the existing foundation and cause it to shrink even more.

Mastic rubber-bitumen MRB for roofing and foundation, cold application, quick-drying 1.8 kg.

Strip foundation

The strip foundation is poured in two different configurations: a closed rectangle and an open rectangle shaped like the letter "P."

Connecting the extension to the house’s foundations comes in a few different forms:

When using a closed technique to pour concrete:

• install a 50 mm thick expanded polystyrene sheet between the foundation strips. It will be part of the formwork when pouring concrete. After filling, the remaining gap must be sealed with sealant;
• connect the ends of the foundations with a reinforced frame. At the end of the base of the house, drill holes in two staggered rows. Place reinforcing bars there, which you will later connect to the frame of the extension’s foundation;

Using the technique of open filling:

• pour the foundation of the extension in the shape of the letter “P”, and install insulation on the crack in the house;
• to connect buildings, drill holes for reinforcement only at the junction of two foundations.

Columnar foundation

A columnar foundation is a good substitute for a strip foundation if your extension is lightweight and small in size. This kind of foundation works well for building a frame addition with a lot of groundwater.

Phases of building an extension’s columnar foundation:

1. Dig holes deeper than the freezing level of the soil; the distance between them should not exceed 1.5 meters.
2. Place a bed of sand and gravel at the bottom of the holes. Compact the material well and lay the roofing material.
3. Prepare strong formwork from boards or plywood for each pit.
4. Reinforce the formwork using 4 bars of periodic profile reinforcement.
5. Pour the concrete mixture into the formwork and wait until it hardens completely. Remove the formwork and make a grillage.

Gypsum putty “Finishing” Prospectors, 20 kg

Installation of the base floor of the extension

An appropriate wooden floor base for a columnar foundation is needed. One option for flooring when building a strip base is to use concrete or wood. A level surface and excellent thermal insulation are essential if the extension room is to be utilized as an extra room.

When it comes to strength and durability, concrete floors win out, but wood-framed homes also offer excellent sound and heat insulation. Installing wooden beams is also quicker and simpler.

Concrete floor

Take into account the properties of the extension soil prior to pouring the floor. On loose soil, a concrete floor is not put in. The concrete structure might eventually deteriorate if the room is never heated.

When building a concrete floor, the following procedures are involved:

1. After the strip foundation has completely dried, dig out the top layer of soil inside the structure by 25-35 cm and compact the surface of the earth.
2. Fill in river sand 10 cm thick. Tamp and lay two layers of roofing felt in a checkerboard pattern.
3. Fill in expanded clay to a thickness of 15 cm. Install special beacons or bricks along the perimeter of the expanded clay cushion. Install a building level on top and level the base of the floor. If the extension is being built for a summer cottage, it is not necessary to lay the reinforcement grid.
4. Pour in high-quality concrete mortar, level it with a rule and wait for it to harden completely.

Floor on wooden beams

Load-bearing joists must be installed for a frame extension or a columnar foundation structure. They serve as the extension’s equivalent of the building’s skeleton, dispersing weight uniformly.

These technologies are used in the laying of beams:

1. Install and secure a double layer of waterproofing on the foundation pillars.
2. Before installation, treat wooden beams with a special antiseptic.
3. Lay the floor beams on the foundation pillars and secure them with corners. Fasten the beams together in the same way.

Unis Reinforced Gorizont base mixture

Erecting the walls of the extension

The same material used for the house’s walls is also used for the extension’s walls. The most popular building materials for walls are wood and brick.

It is preferable to join the walls of two buildings without using a rigid connection. Uneven subsidence and fissures may result from the age difference between the old and new walls. After the building’s walls are constructed, leave two to three centimeters between them. This space should then be filled with polyurethane foam.

Frame walls

First-rate lumber and fastening corners are required for the building of frame walls. We attach the frame to the extension’s base using the previously installed supporting components.

It is advised to assemble the wooden components on the ground for convenience and effectiveness of assembly, and then install:

1. First, install the corner posts, fixing them with reinforced steel corners. Fasten the intermediate beams either by the full notch method, or in the same way as the corner beams.
2. Additionally secure the intermediate beams with temporary braces, which must be removed after the complete installation of the walls of the extension.
3. Fasten the upper tier of the frame in the same way as the lower part. For better strength, each beam can be fixed with braces on both sides.
4. After installing the frame, sheathe the outer walls of the extension with wooden boards or plywood sheets.

Construction tarpaulin 100 g/m2 (3×5 m) INTARP

Brick walls

The following steps are included in brick wall technology:

1. Before starting construction, level the foundation with a cement-sand screed. Place a layer of roofing felt on top for waterproofing. Lay the first row of bricks on roofing felt without using mortar.
2. Attach small-diameter reinforcement bars to the brick rows of the main house. Drill holes every two rows of bricks. During the bricklaying of the extension, the protruding reinforcement from the walls of the main house will end up in the seams between the newly laid bricks.
3. Parallel to the wall, pull a rope that will help erect the brick rows as evenly as possible. Between every third row of bricks, you can lay a reinforcement mesh that will reduce shrinkage and increase the strength of the walls.

Once the walls are constructed, use a concrete belt to secure them together from above. Fill the constructed reinforced formwork with concrete mortar.

You may adapt the space to suit your needs and increase the value of your home by building an addition on your own. It can be a satisfying and affordable project. Every step of the process, from laying the foundation to finishing the roof, can be completed with confidence if you have the proper planning, the appropriate supplies, and a basic understanding of construction. With its helpful advice and simple instructions, this guide will lead you through the process of successfully adding that extra room, sunroom, or garage to your house.

Extension ceiling and roofing

Additionally, the extension roof needs to blend in with the main structure. Make sure to choose premium roofing material and figure out the sizes and inclination angles during construction. The ideal inclination angle for metal profiles is from 20º, for slate and slate tiles it is from 30–40º, and for corrugated sheets it is from 12º.

The following steps are part of the roofing process’s technology:

1. Install ceiling slabs in the form of wooden beams on the walls. Fasten them with corners at a distance of 50-70 cm from each other. If the walls are made of brick – embed the beams in concrete. Then sheathe them with boards and insulate.
2. Lay a Mauerlat along the perimeter of the side walls. It will serve as a support for the rafters, which are erected at a distance of no more than 70 cm from each other. There should be the same step between the rafters and the floor beams. To protect the walls from water, the rafters must extend beyond the walls by 30 cm.
3. Put a special waterproofing film on the rafters and install the sheathing in the form of horizontal boards.
4. Place the selected roofing material on the sheathing.

Insulation of the extension from the inside

It is crucial to ensure that the walls, ceiling, and floor of the extension room have excellent thermal insulation if it will be used as a living room. The room’s concrete walls are insulated from the exterior for improved ventilation. Mineral wool or polystyrene foam are suitable materials.

Black construction nails 4×100 mm (5 kg packaging)

Insulation of the floor on the beams

To arrange floor covering and insulation, a subfloor is installed. On the load-bearing joists of the extension, cross boards are installed.

The following stages are included in the additional technology:

1. Put a waterproofing film on the subfloor, on top of which install additional joists.
2. To insulate the floor, lay several layers of polystyrene foam or mineral wool between the additional joists.
3. Put another layer of vapor barrier on top, onto which the oriented strand board sheets will be laid.
4. Install the final floor covering.

Concrete floor

The concrete floor is insulated in the same manner as a wooden floor. On the concrete screed, a layer of waterproofing film is applied. It is possible to install thick joists and use expanded clay to fill in half of their thickness. As a result, there will be more thermal insulation. Then, OSB boards, a second layer of film, and mineral wool are laid using the same plan.

Frame walls

A lathing of wooden bars is made around the outside of the walls and ceiling to insulate frame walls. Mineral wool rolls are used for insulation purposes in the extension. The wool roll and the wooden bar should both be the same thickness. The width of the insulation roll is equal to the spacing between the bars.

We waterproof the surfaces after providing thermal insulation. The waterproof film is nailed to the lathing bars after it is laid in an overlapped pattern. After that, the space is embellished with wooden paneling, plastic, or plywood sheets.

Brick walls

It is possible to insulate the extension’s exterior and interior brick walls. The process of insulating an interior space follows the same guidelines as insulating a frame extension’s walls. Brick walls with external insulation are frequently insulated using foam plastic. Using a unique glue, the insulation is adhered to the building’s exterior walls in a checkerboard pattern.

Dowels are inserted into the walls to provide additional reinforcement for the slabs. After applying a reinforcing mesh on top, the last step in plastering is completed.

TEX latex leveling finishing putty Pro, white, 5 kg

Adding an addition to your home on your own is a worthwhile and economical project. You can add extra living space that suits your needs and raises the value of your house with thoughtful planning and a firm grasp of the building process. With this project, you can design the area exactly how you want it, making sure it blends in perfectly with the current building.

It is essential to adhere to local building codes and secure the required permits at every stage of the process. This guarantees the security and legal compliance of your extension. Additionally, a sturdy and dependable structure will be produced by utilizing high-quality materials and appropriate construction methods. If you’re unclear about any aspect of the project, don’t be afraid to consult reputable sources or professionals for advice.

Feel proud of the work you’ve done as you finish your extension. You’ve not only increased the size of your living area but also acquired useful knowledge and abilities in construction. It can be a really fulfilling experience, and it might even encourage you to take on more do-it-yourself tasks in the future. Recall that finishing a home extension successfully requires perseverance and patience.

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