Renovation

Balcony glazing for renovated buildings

Residents of apartment building associations eagerly await government funds that would accelerate renovation programs for residential buildings. Association chairpersons aim to find technical solutions that offer an acceptable balance between cost and quality for the majority of members. The primary focus is on key energy-saving measures: window replacement, wall insulation, roof and heating system upgrades. Most projects are typically carefully prepared by experienced professional designers or companies specializing in residential building renovations.

To help ease the initial workload of association chairpersons, we would like to share our experience in choosing balcony glazing solutions, which also constitute a significant part of residential building renovation projects.
When considering which balcony type would best suit your residential building, it is always important to evaluate several aspects that influence the correct choice of balcony glazing, including the technical possibilities for balcony glazing in the building planned for renovation:

What materials were used in the existing lower balcony railing structures?

If black metal was used, does its condition still meet safety requirements?

If the lower part of the balcony is made using metal structures and concrete slabs – what is their condition?

Is it possible to attach new finishing materials to the existing metal structures?

After conducting these assessments, it is possible to decide whether a full balcony renovation is needed or if it is sufficient to glaze only the upper part of the balcony.

It is also important to know which materials are planned for insulating the main building walls. This will allow you to assess whether it is possible to implement wall insulation while retaining the existing balcony railing.

As you may have noticed, we have divided balcony glazing into two parts: the lower balcony railing section and the upper balcony glazing section.

Apatinė balkono dalis

This is a stationary external balcony barrier, which, according to current STR (Technical Regulations), should be no less than 1100 mm in height, made of well-processed metal or using ALU profiles. Vertical posts should be spaced no more than 1200 mm apart. All vertical posts should be connected by a continuous profile called a handrail. If no decorative finishing elements are planned between the vertical posts and the lower part is to be glazed, the glass must be laminated, 424 mm thick, according to the STR valid in Lithuania. Instead of glass, various other covering materials can be used, such as dibond, cetris, etc. It is not recommended to use polycarbonate sheets, acrylic glass, or other plastics, as their rigidity strongly depends on temperature fluctuations, and under Lithuanian climatic conditions, these materials are not the most suitable.

Upper balcony glazing part

This is a balcony glazing structure that is mounted on the stationary lower part of the balcony. The choice of this glazing system greatly affects the facade appearance of the building, the practicality of balcony use and maintenance, somewhat the overall sound insulation of the apartment, ventilation options, opening and closing methods, and visible space. The upper balcony glazing structure can be divided into three main types:

Frameless glazing system
ALU framed sliding system
Manufactured using PVC profiles (plastic window principle)

Frameless, fully opening, balcony glazing system

This type of glazed balcony system model came from Scandinavian countries. It gained popularity in Lithuania due to several simple characteristics. In balconies there are no profiles between the glass panels, so the overall facade appearance of the entire building looks impeccable. A balcony glazed in this way looks light, transparent, and spacious. This appeals to many architects and designers. However, the main advantages are best appreciated by the direct user, so the improvement of the frameless balcony system took place over several decades. All glass sections slide with the help of rollers on the upper and lower aluminum tracks in one plane and can open inward to the balcony like book pages, where they are secured. This way they take up little space and become immovable even in strong wind. The balcony can be opened 100 percent. The frameless glazing system has an advantage over other balcony glazing systems in terms of both ease of use and maintenance. To clean a balcony glazed with a frameless system, you simply need to push each washable panel to the wall and open it. This way cleaning the glass is both easy and safe.

All glass panels in the frameless balcony system are made from 6mm tempered glass. The edges of the particularly strong glass are polished, so maximum safety level is achieved when using the product. There is no need to mount the glass into additional frames or glue impact-resistant films. 6 mm tempered glass resistance withstands up to 425 MPa pressure, while ordinary 6 mm glass resistance withstands up to 150 MPa pressure. When breaking, tempered glass shatters into small pieces. This protects people from cuts that can occur when using ordinary glass. The entire weight of the glass is supported by the upper load-bearing profile, so attention must always be paid to whether the upper profile can be attached so that it aligns with the plane of the lower balcony parapet.

The main aluminum profiles of this system are adapted for mounting any water drainage gutters, so it is quite simple to adapt to various construction situations and find the best solutions. In the frameless balcony system there are no side profiles attached to the wall at all, so during installation the insulated and decorated wall surface is not damaged at all and no additional finishing work is needed.

Normally, vertical 3-5 mm gaps remain between the closed glass panels, through which during heavy rain and unfavorable wind, a small amount of precipitation can enter the balcony interior. To solve this problem, special transparent plastic spacers 15 mm wide are mounted between the glass panels, which ensure complete balcony sealing. If you want the balcony glass to be closed while the balcony naturally ventilates, these spacers can be easily removed.

The frameless glazing system can also be mounted from the bottom of the balcony to the top. This way terraces, verandas, or vestibules can be glazed. When glazing balconies, the lower part of the balcony parapet should remain, and this frameless system would be mounted with the structure slightly recessed into the balcony interior. The maximum height of this structure can be up to 2900 mm. In this case, the glass sections will be manufactured using 8 mm tempered glass and the balcony glass will open 100 percent.

ALU framed sliding balcony glazing system

This system is distinguished by the fact that all glass sliding parts are in aluminum profile frames. Therefore, according to the STR in force in Lithuania, ordinary 4-6 mm thick glass can be mounted in framed structures. The sliding parts move very easily on specially mounted profiles. The entire weight of the sliding parts is supported by the lower load-bearing profile. The frame width when viewed from the inside of the balcony is 50 mm, slightly narrower than balconies made using PVC profiles.

This system is airtight, has special locking mechanisms, adjustment capability, and all the necessary profiles that allow glazing in various configuration balconies. If the framed balcony glazing system is mounted on the lower balcony parapet, the widths of the opening parts should be carefully coordinated to match the visible divisions of the lower part. Otherwise, the balconies in the overall context of the renovated building may look very asymmetrical. The operation of this type of balcony is quite convenient. To clean the exterior glass, each sliding part together with the glass is lifted out of the general frame. It is placed inside the balcony, cleaned, and inserted back into its original place. The size of the sliding part should be no more than 2 sq.m., then the weight of one part will be about 15 kg and its lifting or placement will become simpler, reducing the risk of breaking the glass. When mounting this type of construction from the bottom of the balcony to the top, the overall rigidity of the structure should be well evaluated and, if necessary, additional rigidity profiles should be included. In such structures, the glass in the lower part, according to the STR in force in Lithuania.

Balcony glazing using PVC profiles

Many residents have independently renovated their balconies using this balcony glazing method. The main advantages of this system are that window production from PVC profiles in Lithuania is very well developed. You can quite easily find a reliable company that will perform all the agreed work. It remains to decide on the location and quantity of opening and non-opening windows, which most often determine the overall balcony glazing price, clarify the planned water drainage work, and don’t forget to discuss finishing work. Most often when glazing a balcony this way, a double-glazed unit is used, one of which has a selective coating. It is not advisable to save money by using only one glass pane in PVC profile frames. Since this system is the most airtight, in winter you may see frosted or condensation-covered balcony window glass through your apartment windows, and the savings will definitely not be worth it.

Balconies come in very different sizes and configurations, even in older construction buildings, so it is very important to pay attention that all mandatory window connection profiles are used. Most often, the installation quality and the selected water runoff slope forms determine whether unwanted moisture will enter your balcony.
A balcony glazed with PVC windows has better sound insulation properties and better isolates cold from entering the balcony interior. However, it should not be forgotten that a balcony is not a heated room, so to avoid glass condensation, the ventilation mechanisms installed in PVC windows should be actively used.

The width of a PVC window frame is about 70 mm, and the total frame width of an opening window is about 110 mm, so when planning the location of opening windows in larger balconies, attention should be paid to ensure there are no connection profiles between the opening window frames, because in that case you will see a plastic frame about 220 mm wide from your balcony. Most often, non-opening display windows are mounted between PVC opening windows. This avoids additional profile thickening and aims to ensure that through a fully opened window, the glass of the non-opening window can be reached for cleaning from the outside. Such window cleaning is not very convenient, but with modern tools designed for this purpose, it is fully possible.

When glazing a balcony with PVC profile constructions from the bottom of the balcony to the top, the lower part of the balcony should be filled using thermal sandwich panels or glazed using a glass unit with laminated glass. The standard balcony height is about 2700 mm, so all window manufacturers, aiming to ensure structural stability, use connection profiles with additional rigidity ribs and reinforcement.

What influences the balcony glazing price?

Now we can talk a bit about one of the most important questions that arises for all residents – what primarily influences the balcony glazing price?

As you noticed, we have already tried to divide balcony glazing into two parts. That is, the lower balcony parapet part and the upper balcony glazing part. In renovated buildings, the price most often depends not so much on the choice of the upper glazing system for balconies, but on the choice of technical solutions. It can even be stated that the choice of the upper balcony glazing system will have small and not so significant price differences in the overall budget for the building’s balcony glazing.

Primarily, the price of renovated balconies is influenced by decisions related to the renovation of the lower balcony parapet part. When calculating how much balcony glazing costs per square meter, you will almost always notice that the lower part of balcony glazing is significantly more expensive than the upper part of the balcony glazing. This happens because the lower part uses significantly more metal or aluminum profiles, rigid parapet fixing parts are needed, and various solutions are sought for covering the lower part of the balcony. For example, when choosing not transparent but tinted glass for the lower part of the balcony, it should be taken into account that the glass will need to be not only laminated but also tempered. Ordinary laminated glass with one or another tint shade can crack due to temperature fluctuations.

The cheapest option is when the technical condition allows leaving the lower balcony parapet as it is and only mounting a new upper balcony glazing system. A slightly more expensive option is when the existing main parapet structures can be used, using some additional profiles and adapting new finishing materials to the existing parapet. The most expensive option is when the existing lower balcony parapets need to be completely dismantled and replaced with new ones.

Good solutions for renewing the lower part of the balcony can save a large portion of the money allocated for balcony renovation. Everything depends on the existing situation in the building being renovated. After evaluating balcony configurations, dimensions, and design possibilities, cheaper technical solutions can be found, even using aluminum profiles instead of black metal. It cannot be stated that this always works, but experience shows that each building being renovated requires individual solution searching. And to perform all work well, you should not spare your time for consultations with several companies that specialize in certain areas.