PVC window installation in Seixal
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- Town
- Seixal
- District
- Setúbal
- Position
- 38°39′ N · 9°06′ W
- Tilt and turn: opens to the side and tilts for fresh air.
What will it cost? Start with the sizes
Window type
Material
Colour
Sizes
Between 600 and 1800 mm
Between 300 and 2200 mm
A rough size is fine.
Extras
Window schedule
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About Seixal
Seixal lies on the south bank of the Tagus, around a bay that is a large arm of the river. The Corroios salt marsh is to the west and the Judeu river to the east. In 2021 it had 166,525 inhabitants. The bay and the streams that feed it are part of one of the most important wetlands in the country and a National Ecological Reserve.
The name comes from “seixo”, the smooth stones of the river. The bay has been inhabited since Roman times, and in the 15th century the Seixal yards built river boats and ocean-going ships. It was here that Vasco and Paulo da Gama had vessels built for the voyage to India. A tide mill had worked at Corroios since 1403.
In the 18th century Seixal was a summer retreat for the Lisbon nobility, and manor estates such as Fidalga, Álamo and Trindade remain. In the 19th century factories arrived around the bay: glass at Amora, woollens at Arrentela, cork at Seixal and cod drying at Ponta dos Corvos. About 100 years ago, it was the country’s main cork centre.
The Siderurgia Nacional steelworks opened in 1961 and the bridge over the Tagus, in 1966, brought Seixal closer to Lisbon. The town is flat, with a cycle path along the bay linking Amora to Seixal. Among bay, marsh, old estates and apartment blocks, windows in Seixal live more on damp than on salt.
What the climate of Seixal asks of windows
Wikipedia has no climate section for Seixal. The municipality is on the south bank of the Tagus, a few kilometres from the Atlantic, so the climate of the Lisbon and Setúbal peninsula region applies: Mediterranean, with hot, dry summers and mild, damp winters. The bay and the marsh, which are protected wetland, make the air damper in the morning and at night. On flat ground with no slopes, the wind runs over the water and reaches the houses.
Seixal sits around a bay of the Tagus, on flat ground. The air is damp and the wind runs freely.
Salt is weaker than on the coast, but the damp is strong. The drawing shows a house by the bay.
- Bay wind
The town is flat and opens onto a wide bay, with no high slopes to stop the air. The wind runs over the water and reaches homes by the river, in Arrentela, Seixal and Amora. On gusty days, small gaps in the frames whistle and let in cold.
- Brackish bay air
The estuary is salty, but less than the open sea. Even so, damp bay air settles on metals and wears down weak hardware. In Amora and Seixal, rinsing the windows with fresh water now and then is a good habit, especially in homes by the water.
- Marsh damp
By the Corroios marsh and the Judeu river, which are protected wetlands, the air is damp for much of the year. Mould shows up in cold corners and behind furniture, and the glass is wet on colder mornings. Windows that insulate well and daily ventilation are the first defence.
- Sun without shade
On flat ground with little shade, the summer sun heats south- and west-facing facades, and the house keeps the heat. Outside blinds, light colours and glass with a solar coating hold back part of it. The bay breeze also helps to air the home at night.
| Condition | Level | Climate sheet |
|---|---|---|
| Summer | High | Hot, on flat ground with little shade. |
| Winter | Medium | Mild; damp cold by the bay. |
| Rain | Medium | More in autumn and winter. |
| Wind | Medium | Runs over the bay, with no slopes to stop it. |
| Humidity | High | High by the bay and the marsh. |
| Sun | High | Plenty of summer sun. |
Levels for comparison, not measurements.
SourcesWikipédia: Seixal
Climate zone of Seixal
Portugal's building energy rules put every place in a winter zone (I1 to I3) and a summer zone (V1 to V3). In Seixal the zone depends on the altitude of the building, so we show the ranges.
| Building altitude | Winter zone | Maximum Uw, W/(m²·°C) |
|---|---|---|
| up to 217 m | I1 | 2.80 |
| from 218 to 550 m | I2 | 2.40 |
| above 551 m | I3 | 2.20 |
Summer zone: V3: up to 206 m; V2: from 207 to 606 m; V1: above 607 m
Maximum solar factor of windows (gtot,máx): up to 206 m, V3: 0.10 in weak-inertia spaces and 0.50 in medium or strong inertia spaces; from 207 to 606 m, V2: 0.10 in weak-inertia spaces and 0.56 in medium or strong inertia spaces; above 607 m, V1: 0.15 in weak-inertia spaces and 0.56 in medium or strong inertia spaces. The value is for the opening with the solar protection fully activated. North-facing windows are exempt. What is the solar factor?
The maximum Uw applies to windows in housing in new and renovated buildings (Portaria n.º 138-I/2021), with exceptions, for example conservation works. The zone is calculated with the Manual SCE method, from the region (NUTS III) and the altitude, not by parish. Ask the designer or an SCE expert to confirm the one for your building. Checked on 19 October 2026. What is Uw?
Solutions table for Seixal
| Window | Glass | |||
|---|---|---|---|---|
| Local condition | PVC | Aluminium | Double glazing | Triple glazing |
Bay wind | SuitableGood. The wind is moderate, so a well-done installation is enough. | SuitableHolds up well. Check the seals at the corners. | SuitableWind matters little when choosing the glass. | It dependsOnly worth it if the rest of the window is good. Ask. |
Brackish bay air | SuitableThe frame does not rust. A good choice near the water. | It dependsFine with a good finish. Clean it now and then. | SuitableGlass copes well with estuary air. | SuitableSame as double glazing on this point. |
Marsh damp | SuitableGood against cold and damp near the water. | Needs careFine with a thermal break. Without one, condensation may appear. | SuitableGreatly reduces water on the glass, even by the salt marsh, with airing. | It dependsCosts more. Makes sense in cold, north-facing rooms. |
Sun without shade | SuitableGood all year. Light colours help in summer. | SuitableWorks well. A light colour heats up less. | SuitableA good choice for both sun and cold. | It dependsGives more comfort. Summer gain depends on the orientation. |
- Suitable
- Needs care
- It depends
By the marsh, the installer should talk about ventilation and condensation. The rest is confirmed on site.
Homes in Seixal
The homes in the area change what is worth asking of the windows.
Historic centre
The old core of Seixal, near Praça Luís de Camões, Pátio do Genovês and Largo da Igreja, has old houses and small streets. The old wall rules the edge finish, and the installer should measure on site. Ask the council whether the area has rules.
Detached and semi-detached houses
There are former manor estates, such as Fidalga and Álamo, and houses from many periods. Every opening is different, and the windows of an old house rarely repeat the same size. Ask for a visit and written proposals.
New apartments
In Amora, Corroios and Fernão Ferro, growth in recent years may have brought apartment blocks and developments. There the sun on the facades and damp weigh, and seals and ventilation count most.
How it works
Tell us what you need
Measure the opening on the drawing and confirm your town.
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We do not make or fit windows. We pass your request on and explain.
Towns near Seixal
Do not live right in Seixal? These are the neighbouring municipalities and three parishes of the municipality.
Cannot find your area? Write it in the request.
Flat town by the bay
With no slopes to slow the air, the bay wind reaches the houses unobstructed. Near the marsh, the air is damp in the morning and at night. Seals, the edge finish with the wall and daily airing count. In homes by the water, ask the installer to check the outside finish and the frame drainage, because wind-driven rain gets in there. A window with good insulation leaves the inner glass less cold, which reduces condensation in the cold months. Also ask that the frame drainage holes stay clear after the job.
Estates, shipyards and factories: homes with history
Seixal was a place of shipyards, tide mills and big factories, and was left with many estates and old houses. In an old house, walls and openings are not straight, and new windows have to fit them. Ask the installer to measure on site, ask how the edge finish will be done and whether the window can keep a design close to the original. In estate houses, a new window can keep the divisions and the look of the old frame, if the profile is chosen with care. Talk to the installer about that.
General notes
It is the main issue, because marsh air is damp for much of the year. Windows that insulate well, daily ventilation and a well-treated shutter box help avoid mould. Avoid drying laundry indoors.
They do. PVC does not rust, and aluminium needs a good finish. Hardware is metal and appreciates a fresh-water rinse now and then. Bay air is less salty than open sea air.
Usually yes, but ask Seixal town council whether the area has rules. The installer should measure each opening on site, because the walls are irregular. Ask for a written proposal.
Yes, there is little shade. Outside blinds and glass with a solar coating hold back the heat. Light colours on the frame heat up less. At night, the bay breeze helps air the home.
It should not be. It is almost always a gap in the seal or the latch. A well-installed window ends the whistle. If the window is recent, speak to the installer again.
Yes. Give your parish in the request, and say whether the house is near the bay or further inland. JanelaCerta does not install windows: it passes the request to installers in the area.
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