How to Frame an Oil Painting Without Ruining It

Oil paintings are built to last centuries, but a bad frame job can cause damage in weeks.

To frame an oil painting without ruining it, you need the right frame style, accurate measurements, no glass directly against the surface, and secure fitting hardware that doesn’t stress the canvas. Get any one of those wrong and you risk warping, cracking, or permanently marking your painting.

At Mobile Framing, we’ve seen it all and most of the damage we’re called in to work around was completely avoidable. That’s why we’ve put together this guide. These are the same tips our framers use every day, written so you can approach your next frame oil painting project with confidence and without costly mistakes.

Why Oil Paintings Need Special Framing Attention

Oil paintings behave differently from prints, photos, or watercolours.

The paint sits on top of the canvas in raised layers. It expands and contracts with changes in temperature and humidity. And unlike paper-based artwork, oils are almost never framed behind glass. Which means the frame itself does more of the protective work.

This is why you can’t just pull any frame off a shelf and expect it to work. A frame oil painting project requires thought before a single measurement is taken.

Pick the Right Frame Style First

The frame style you choose affects both the look of the painting and how safely it can be fitted.

Float Frames – the Modern Favourite for Oils

A float frame is the most popular choice for contemporary oil paintings, and for good reason.

The canvas sits inside the frame with a small visible gap around all four edges. This means:

• The frame never touches the painted surface
• The canvas has room to expand and contract naturally
• The full painting, including the edges remains visible

Float frames are particularly well suited to paintings on deep-profile canvases. They’re also forgiving if your canvas isn’t perfectly square, which is more common than most people expect.

Traditional Frames – When They Work and When They Don’t

A traditional rebated frame wraps around the front edge of the canvas and holds it from behind.

This style works well for oil paintings on board, or for thinner canvases where a classic look is preferred. However, it requires very precise sizing. If the rebate is too tight, it puts pressure on the stretcher bars. Too loose, and the painting can shift and knock against the frame over time.

For traditional frames, the fit needs to be snug but never forced.

Measure Before You Buy Any Frame

Incorrect measurements are the number one reason a framing job goes wrong.

Canvas Depth vs Rabbet Depth

The rabbet is the inner lip of the frame, the part the canvas rests against or sits inside. Before buying any frame, you need to know two things:

• Canvas depth – how thick your canvas and stretcher bars are combined
• Rabbet depth – how deep the frame’s inner channel is

The rabbet depth must be equal to or greater than the canvas depth. If the canvas is deeper than the rabbet, it will protrude beyond the back of the frame. This makes it impossible to hang flat against the wall and puts uneven stress on the frame joints.

Many customers visiting Sydney picture framing studios bring in a painting without these measurements. Always measure both before you go shopping or order online.

Why a Loose Fit Can Damage Your Painting Over Time

A frame that’s too large is just as problematic as one that’s too tight.

A canvas that is loose in a frame rattles and moves with every vibration – foot traffic, closing doors or even air conditioning units. Over time, this movement causes the canvas to rub against the frame interior, wearing away paint at the edges and potentially cracking dried paint layers.

The ideal fit allows very slight movement for natural expansion but holds the canvas firmly enough that it doesn’t shift freely.

Should You Put Glass Over an Oil Painting?

This is one of the most common questions we hear, and the answer is almost always no.

Oil paintings need to breathe. Sealing them behind standard glass traps moisture, which leads to mould, flaking, and surface deterioration. Unlike works on paper, oils don’t need glass for structural protection.

There are two exceptions worth knowing:

• UV-filtering glass or acrylic can be used if the painting is in a high-light environment and a gap spacer is used to keep the glazing off the paint surface
• Pastels or mixed media that include oil paint may still require glazing, assess each piece individually

If you’re unsure, ask us, as an experienced picture framers in Sydney, we will always advise against standard glass directly over an oil painting.

How to Fit and Secure an Oil Painting in a Frame

Once you have the right frame and the measurements are confirmed, fitting the painting correctly is the final critical step.

Using Offset Clips the Right Way

Canvas clips, also known as turn buttons or offset clips, are the standard hardware for attaching a canvas to a frame. They screw into the back of the frame and fold over the stretcher bar to hold the canvas in place.

When fitting:

• Space clips evenly, at least two per side on smaller works, more on larger pieces
• Tighten firmly but not excessively. Because over-tightening bends the clip and creates pressure points on the stretcher bar
• Check that the canvas sits flat before securing all clips

Never use staples, nails through the canvas, or adhesive tape to hold an oil painting inside a frame.

What Not to Touch on the Canvas Surface

Even clean hands carry oils that can affect paint over time.

When handling the painting during fitting:

• Grasp it by the stretcher bars in back – not by the painted surface
• If you have to put it face down for a short time, place it on a clean, soft cloth that is  never directly on a hard surface
• Avoid pressing on the canvas from the front at any point during the process

It can be difficult, sometimes impossible, to undo one accidental thumb print or dent in a new fitted canvas.

Protect Your Painting for the Long Term

Framing is just the first step in protecting a painting. Once it’s framed and hung, a few simple habits make a significant difference.

• Avoid direct sunlight – UV light fades pigment over time, even in oils
• Keep away from humidity sources – bathrooms, kitchens, and exterior walls with poor insulation are all risk zones
• Dust the frame regularly – dust build-up around the rebate edges can work its way onto the canvas surface
• Check the hanging hardware annually – D-rings, wire, and wall fixings all wear over time

If your painting is worth anything, whether money or sentimentally, you might want to have it checked out by a professional every few years. Many Sydney picture frames specialists offer condition checks as part of their service.

Not Sure? Let a Professional Framer Take a Look

Some paintings are straightforward to frame. Others like large canvases, antique works, unusual shapes, or pieces with sentimental value, deserve a professional eye before anything is decided.

A professional framer will assess the canvas condition, recommend the right frame profile and depth, and fit everything correctly the first time. That’s not just a convenience. For an irreplaceable painting, it’s the safest choice you can make.

Frame Your Oil Painting With Confidence

Framing an oil painting correctly comes down to four things: the right frame style, accurate measurements, no glass against the surface, and careful fitting with the right hardware.

Get those right and your painting is protected for decades. Get them wrong and the damage can be swift and permanent.

At Mobile Framing, we come to you. Our framers bring everything needed to assess, advise, and frame your oil painting on-site with no damage from moving a precious piece across town. Whether you have a single painting or a full collection, we make the process simple.