Plaster and Render Finish Questions Checklist

Write down what you know about how the wall is built, including anything discovered during earlier work, and hand that to whoever is advising you.

Owners often hold useful history about a wall that nobody thinks to ask for.

Note what is on the wall now, including old plaster, previous coatings, tile adhesive residue and any paint that has been applied over the years.

What is already there decides how much preparation is needed and whether it can be worked over at all.

Tap gently across the wall, note any areas that sound hollow or feel loose, and point those out rather than assuming they will be noticed.

Hollow areas are the most common reason a new finish fails, and they are easy for an owner to identify roughly.

Describe any history of moisture, staining, salts or blistering paint plainly, and ask a qualified professional to look before a finish is chosen.

Moisture is a diagnosis rather than an observation, and the finish choice depends entirely on it.

Staining, salts and blistering are symptoms a qualified professional needs to see on the wall itself before any finish is chosen for it.

If the building is older or built in solid construction, ask which finishes the professional considers appropriate for that kind of wall and why.

Traditional and modern finishes behave differently on older walls, and this is a specialist conversation worth having early.

What an older or solid wall requires is a specialist matter for qualified professionals familiar with that form of construction.

Ask which family of finish is being proposed, whether a plain surface intended for painting, a polished decorative plaster or a textured applied finish.

The trade, the preparation and the way the result is judged all change with the family.

For any decorative finish, ask who applies it, whether that is the same person doing the ordinary work, and see examples of their own hand.

Decorative finishes are the work of an individual, and two applicators produce visibly different surfaces.

Look at how much sheen and depth the finish has, and view an example both straight on and at a shallow angle.

Polished finishes change completely with the viewing angle, which never shows in a photograph.

Ask how a textured or decorative finish is cleaned, and what happens where a hand, a chair or a bag rubs against it regularly.

Textured walls in a hallway or beside a dining table take more contact than people expect.

If a decorative finish is proposed near a bath or a shower, ask specifically what the applicator says about water contact in that position.

Decorative finishes vary in how they deal with water, and the position needs describing plainly.

Whether a decorative finish belongs anywhere near a bath or a shower is for the applicator and a qualified professional to answer about that wall.

Ask how corners, reveals and edges are formed in the chosen finish, and look at those details on an existing example.

The quality of a plastered wall is judged at its corners more than across its open face.

Ask for a sample panel to be made on the actual wall, by the person who would do the work, before the whole room is committed.

The panel tests the applicator, the background and the light all at once.

Ask for the panel to be generous rather than small, since a hand-applied texture cannot be read from a patch the size of a book.

Small samples hide the rhythm of a texture and the variation across an area.

Live with the panel through changing weather and through evening light before agreeing that it represents the finish you want.

Decorative finishes look quite different in bright daylight, in dull weather and under evening lamps.

Photograph the agreed panel, note what it is, and record in writing that it represents the standard for the finished work.

A recorded reference point resolves disagreements that are otherwise a matter of memory.

Ask whether the panel can be left in place until the work is complete, so the finished surface can be compared against it.

Panels are usually covered over immediately, which removes the only physical reference you had.

Identify every light that will graze along a wall, including downlights close to it, wall lights and low sun through a window.

Light travelling parallel to a surface exposes undulations that are invisible in flat light.

Raise the lighting positions with both the plasterer and whoever is fitting the lighting, before either is finalised.

Moving a light away from a wall is far easier than making a wall flat enough to survive it.

Ask the plasterer to describe what standard of flatness is achievable on this particular background and what that means in practice.

An old wall and a new board background give quite different results, and expectations should follow the background.

Look at finished work in the same light conditions you discussed, rather than at a moment of the day when the wall happens to look flawless.

A wall seen under a work light at night can look perfect and then look disappointing the following afternoon.

Ask how the intended paint sheen interacts with the surface, since a more reflective finish shows more of what lies beneath it.

Paint choice and plaster quality are related decisions that are usually made by different people at different times.

Ask which hairline cracks and shrinkage lines the plasterer would consider normal for this finish and this background.

Fine cracking at junctions is common, and knowing that in advance changes how it is received.

Ask what happens where the finish crosses a junction between two different materials, and whether anything is done at those lines.

Cracks appear where materials meet far more often than in the middle of a wall.

Ask what has to happen before the wall can be decorated, how you would know that stage is reached, and who decides.

Decorating too early is a common cause of paint problems and it is entirely avoidable.

Ask what the applicator advises about heating and ventilation in the room while the finish settles.

Forcing a room warm or leaving it sealed both affect how a finish behaves as it dries.

Agree who deals with any settlement cracking that appears after completion, and how that would be raised.

This is easier to agree while everyone is still on good terms than after a crack has appeared.

Agree in writing with the contractor who attends to settlement cracking after completion and how it is reported.

Look at the intended colour on a large panel outdoors rather than on a card, and view it from the distance people actually see the house.

Colour intensifies dramatically at building scale, and a card is the worst possible reference for it.

Ask whether the colour runs through the render or is painted onto it, and what each means when the surface is chipped or repaired.

A through-coloured render hides small chips that a painted one reveals, and their upkeep differs.

Ask what tends to happen on shaded or north-facing elevations, and whether any part of the building stays damp longer after rain.

Algae and darkening concentrate on shaded, sheltered and overhung elevations.

Note where trees, hedges and planting sit against the walls, and ask what that proximity means for the finished surface.

Vegetation close to a wall keeps it damp and shaded, which shows on render before anywhere else.

Ask how the texture proposed holds dirt, and compare a smooth and a textured example on the same elevation if you can.

Texture and colour together decide how quickly a wall looks tired rather than either alone.

Ask how the render can be cleaned when it does discolour, and whether cleaning affects the colour or the surface itself.

Some cleaning methods lighten or damage a render, which is worth knowing before the first attempt.

Stand outside during or after heavy rain and note where water runs down or off the building, and where it splashes back.

Staining patterns follow these paths precisely, and they are visible on almost any existing building nearby.

Ask how water is thrown clear at window sills, copings and any horizontal ledge, and what happens to the wall directly beneath.

Dark streaks below sills are the most recognisable render staining and they follow from these details.

How water is dealt with at sills, junctions and edges is a matter for qualified professionals, not an owner decision.

Note the position of gutters, downpipes and overflows against the rendered wall, and ask what happens where they discharge or leak.

A single dripping joint marks a rendered wall permanently in a very visible line.

Ask where the render stops at the base of the wall, at openings and at any junction with another material, and what forms that edge.

Terminations are where render is most vulnerable and where the detail is most visible.

Look at what sits against the base of the wall, such as paving, gravel or planting, and ask what splashing does to the finish there.

The lowest part of a rendered wall takes the most punishment and is the first to look poor.

Ask how visible a patch repair would be in this finish, both immediately and once the surrounding surface has weathered.

A patch that matches on the day rarely matches a wall that has aged around it.

Write down the finish name, any colour reference and a description of the texture, together with who applied it, and file that with the house papers.

A repair to a hand-applied finish begins with knowing exactly what is already on the wall.

Ask whether a small quantity of the finishing material can be left with you, and how it should be stored.

A leftover quantity from the original work is the closest thing to a genuine match.

Ask what happens to the finish if a cable, pipe or fixing has to go into the wall afterwards, and whether that repair would show.

A single socket added later can leave a visible line across a decorative wall.

Note who would carry out a repair in this finish and whether that skill is generally available locally.

Specialist finishes need the same specialism to repair, and that is worth knowing before choosing one.